diff --git a/address.go b/address.go
index 5407ac12..667c98a7 100644
--- a/address.go
+++ b/address.go
@@ -128,7 +128,7 @@ func scriptToAddrHashTemplate(script []byte, validformats []pkformat) (ScriptTyp
 	if success == false {
 		if len(script) > 1 {
 			// check for a few special case
-			if script[len(script)-1] == OP_CHECK_MULTISIG {
+			if script[len(script)-1] == OP_CHECKMULTISIG {
 				return ScriptStrange, nil, nil
 			}
 			if script[0] == OP_0 && (len(script) <= 75 && byte(len(script)) == script[1]+2) {
diff --git a/address_test.go b/address_test.go
index 12b3be42..38d9c6cd 100644
--- a/address_test.go
+++ b/address_test.go
@@ -146,7 +146,7 @@ var addressTests = []addressTest{
 		0xa7, 0xa8, 0x45, 0xbd, 0x25, 0x68, 0x9e, 0xdb,
 		0x72, 0x3d, 0x5a, 0xd4, 0x06, 0x8d, 0xdd, 0x30,
 		0x36,
-		btcscript.OP_CHECK_MULTISIG, // note this isn't a real tx
+		btcscript.OP_CHECKMULTISIG, // note this isn't a real tx
 	},
 		addrhash: nil,
 		class:    btcscript.ScriptStrange,
@@ -305,7 +305,7 @@ var multiSigTests = []multiSigTest{
 		0x0e, 0x4e, 0xf8, 0x55, 0x19, 0x46, 0xd8, 0xa5,
 		0x40, 0x91, 0x1a, 0xbe, 0x3e, 0x78, 0x54, 0xa2,
 		0x6f, 0x39, 0xf5, 0x8b, 0x25, 0xc1, 0x53, 0x42,
-		0xaf, btcscript.OP_2, btcscript.OP_CHECK_MULTISIG},
+		0xaf, btcscript.OP_2, btcscript.OP_CHECKMULTISIG},
 		class:   btcscript.ScriptMultiSig,
 		reqSigs: 1,
 		addrhashes: [][]byte{
@@ -342,7 +342,7 @@ var multiSigTests = []multiSigTest{
 		0x0e, 0x4e, 0xf8, 0x55, 0x19, 0x46, 0xd8, 0xa5,
 		0x40, 0x91, 0x1a, 0xbe, 0x3e, 0x78, 0x54, 0xa2,
 		0x6f, 0x39, 0xf5, 0x8b, 0x25, 0xc1, 0x53, 0x42,
-		0xaf, btcscript.OP_2, btcscript.OP_CHECK_MULTISIG},
+		0xaf, btcscript.OP_2, btcscript.OP_CHECKMULTISIG},
 		class:   btcscript.ScriptMultiSig,
 		reqSigs: 1,
 		addrhashes: [][]byte{
@@ -388,7 +388,7 @@ var multiSigTests = []multiSigTest{
 		0x20, 0x36, 0x63, 0x35, 0x33, 0x63, 0x64, 0x39,
 		0x38, 0x37, 0x31, 0x31, 0x39, 0x65, 0x66, 0x37,
 		0x39, 0x37, 0x64, 0x35, 0x61, 0x64, 0x63, 0x63,
-		0x64, btcscript.OP_3, btcscript.OP_CHECK_MULTISIG},
+		0x64, btcscript.OP_3, btcscript.OP_CHECKMULTISIG},
 		class:   btcscript.ScriptMultiSig,
 		reqSigs: 1,
 		addrhashes: [][]byte{
@@ -435,7 +435,7 @@ var multiSigTests = []multiSigTest{
 		0x32, 0x35, 0x36, 0x33, 0x39, 0x64, 0x33, 0x38,
 		0x61, 0x36, 0x63, 0x66, 0x35, 0x30, 0x61, 0x62,
 		0x34, 0x63, 0x64, 0x34, 0x34, 0x0a, 0x00, 0x00,
-		0x00, btcscript.OP_3, btcscript.OP_CHECK_MULTISIG},
+		0x00, btcscript.OP_3, btcscript.OP_CHECKMULTISIG},
 		class:   btcscript.ScriptMultiSig,
 		reqSigs: 1,
 		addrhashes: [][]byte{
diff --git a/internal_test.go b/internal_test.go
index 9d75ce88..0d03b0f7 100644
--- a/internal_test.go
+++ b/internal_test.go
@@ -3544,17 +3544,17 @@ var popTests = []popTest{
 		expectedErr: StackErrInvalidOpcode,
 	},
 	popTest{
-		name: "OP_CHECK_MULTISIG",
+		name: "OP_CHECKMULTISIG",
 		pop: &parsedOpcode{
-			opcode: opcodemapPreinit[OP_CHECK_MULTISIG],
+			opcode: opcodemapPreinit[OP_CHECKMULTISIG],
 			data:   nil,
 		},
 		expectedErr: nil,
 	},
 	popTest{
-		name: "OP_CHECK_MULTISIG long",
+		name: "OP_CHECKMULTISIG long",
 		pop: &parsedOpcode{
-			opcode: opcodemapPreinit[OP_CHECK_MULTISIG],
+			opcode: opcodemapPreinit[OP_CHECKMULTISIG],
 			data:   make([]byte, 1),
 		},
 		expectedErr: StackErrInvalidOpcode,
diff --git a/opcode.go b/opcode.go
index d93f1f8d..241caaf6 100644
--- a/opcode.go
+++ b/opcode.go
@@ -211,7 +211,7 @@ const (
 	OP_CODESEPARATOR            = 171
 	OP_CHECKSIG                 = 172
 	OP_CHECKSIGVERIFY           = 173
-	OP_CHECK_MULTISIG           = 174
+	OP_CHECKMULTISIG            = 174
 	OP_CHECKMULTISIGVERIFY      = 175
 	OP_NOP1                     = 176
 	OP_NOP2                     = 177
@@ -664,7 +664,7 @@ var opcodemapPreinit = map[byte]*opcode{
 		opfunc: opcodeCheckSig},
 	OP_CHECKSIGVERIFY: {value: OP_CHECKSIGVERIFY, name: "OP_CHECKSIGVERIFY", length: 1,
 		opfunc: opcodeCheckSigVerify},
-	OP_CHECK_MULTISIG: {value: OP_CHECK_MULTISIG, name: "OP_CHECK_MULTISIG", length: 1,
+	OP_CHECKMULTISIG: {value: OP_CHECKMULTISIG, name: "OP_CHECKMULTISIG", length: 1,
 		opfunc: opcodeCheckMultiSig},
 	OP_CHECKMULTISIGVERIFY: {value: OP_CHECKMULTISIGVERIFY, name: "OP_CHECKMULTISIGVERIFY", length: 1,
 
diff --git a/opcode_test.go b/opcode_test.go
index 70349be3..6fa50a65 100644
--- a/opcode_test.go
+++ b/opcode_test.go
@@ -381,7 +381,7 @@ var opcodeTests = []opcodeTest{
 		0xa7, 0xdf, 0x5f, 0x14, 0x2c, 0x21, 0xc1, 0xb7, 0x30, 0x3b,
 		0x8a, 0x06, 0x26, 0xf1, 0xba, 0xde, 0xd5, 0xc7, 0x2a, 0x70,
 		0x4f, 0x7e, 0x6c, 0xd8, 0x4c,
-		btcscript.OP_1, btcscript.OP_CHECK_MULTISIG},
+		btcscript.OP_1, btcscript.OP_CHECKMULTISIG},
 		canonical:  false,
 		shouldPass: false},
 	{script: []byte{btcscript.OP_1, btcscript.OP_1, btcscript.OP_DATA_65,
@@ -392,7 +392,7 @@ var opcodeTests = []opcodeTest{
 		0xa7, 0xdf, 0x5f, 0x14, 0x2c, 0x21, 0xc1, 0xb7, 0x30, 0x3b,
 		0x8a, 0x06, 0x26, 0xf1, 0xba, 0xde, 0xd5, 0xc7, 0x2a, 0x70,
 		0x4f, 0x7e, 0x6c, 0xd8, 0x4c,
-		btcscript.OP_1, btcscript.OP_CHECK_MULTISIG},
+		btcscript.OP_1, btcscript.OP_CHECKMULTISIG},
 		canonical:  true,
 		shouldPass: false},
 	/* up here because no defined error case. */
@@ -2162,44 +2162,44 @@ var detailedTests = []detailedTest{
 		nPreciseSigOps: 1,
 	},
 	{
-		name:           "OP_CHECK_MULTISIG no args",
-		script:         []byte{btcscript.OP_CHECK_MULTISIG},
+		name:           "OP_CHECKMULTISIG no args",
+		script:         []byte{btcscript.OP_CHECKMULTISIG},
 		expectedReturn: btcscript.StackErrUnderflow,
-		disassembly:    "OP_CHECK_MULTISIG",
+		disassembly:    "OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 20,
 	},
 	{
-		name: "OP_CHECK_MULTISIG huge number",
+		name: "OP_CHECKMULTISIG huge number",
 		script: []byte{btcscript.OP_PUSHDATA1,
 			0x9, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9,
-			btcscript.OP_CHECK_MULTISIG},
+			btcscript.OP_CHECKMULTISIG},
 		expectedReturn: btcscript.StackErrNumberTooBig,
-		disassembly:    "010203040506070809 OP_CHECK_MULTISIG",
+		disassembly:    "010203040506070809 OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 20,
 	},
 	{
-		name: "OP_CHECK_MULTISIG too many keys",
+		name: "OP_CHECKMULTISIG too many keys",
 		script: []byte{btcscript.OP_DATA_1, 21,
-			btcscript.OP_CHECK_MULTISIG},
+			btcscript.OP_CHECKMULTISIG},
 		expectedReturn: btcscript.StackErrTooManyPubkeys,
-		disassembly:    "15 OP_CHECK_MULTISIG",
+		disassembly:    "15 OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 20,
 	},
 	{
-		name: "OP_CHECK_MULTISIG lying about pubkeys",
+		name: "OP_CHECKMULTISIG lying about pubkeys",
 		script: []byte{btcscript.OP_1,
-			btcscript.OP_CHECK_MULTISIG},
+			btcscript.OP_CHECKMULTISIG},
 		expectedReturn: btcscript.StackErrUnderflow,
-		disassembly:    "OP_1 OP_CHECK_MULTISIG",
+		disassembly:    "OP_1 OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 1,
 	},
 	{
 		// pubkey comes from blockchain
-		name: "OP_CHECK_MULTISIG no sigs",
+		name: "OP_CHECKMULTISIG no sigs",
 		script: []byte{
 			btcscript.OP_DATA_65,
 			0x04, 0xae, 0x1a, 0x62, 0xfe, 0x09, 0xc5, 0xf5, 0x1b,
@@ -2211,15 +2211,15 @@ var detailedTests = []detailedTest{
 			0xba, 0xde, 0xd5, 0xc7, 0x2a, 0x70, 0x4f, 0x7e, 0x6c,
 			0xd8, 0x4c,
 			btcscript.OP_1,
-			btcscript.OP_CHECK_MULTISIG},
+			btcscript.OP_CHECKMULTISIG},
 		expectedReturn: btcscript.StackErrUnderflow,
-		disassembly:    "04ae1a62fe09c5f51b13905f07f06b99a2f7159b2225f374cd378d71302fa28414e7aab37397f554a7df5f142c21c1b7303b8a0626f1baded5c72a704f7e6cd84c OP_1 OP_CHECK_MULTISIG",
+		disassembly:    "04ae1a62fe09c5f51b13905f07f06b99a2f7159b2225f374cd378d71302fa28414e7aab37397f554a7df5f142c21c1b7303b8a0626f1baded5c72a704f7e6cd84c OP_1 OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 1,
 	},
 	{
 		// pubkey comes from blockchain
-		name: "OP_CHECK_MULTISIG sigs huge no",
+		name: "OP_CHECKMULTISIG sigs huge no",
 		script: []byte{
 			btcscript.OP_PUSHDATA1,
 			0x9, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9,
@@ -2233,14 +2233,14 @@ var detailedTests = []detailedTest{
 			0xba, 0xde, 0xd5, 0xc7, 0x2a, 0x70, 0x4f, 0x7e, 0x6c,
 			0xd8, 0x4c,
 			btcscript.OP_1,
-			btcscript.OP_CHECK_MULTISIG},
+			btcscript.OP_CHECKMULTISIG},
 		expectedReturn: btcscript.StackErrNumberTooBig,
-		disassembly:    "010203040506070809 04ae1a62fe09c5f51b13905f07f06b99a2f7159b2225f374cd378d71302fa28414e7aab37397f554a7df5f142c21c1b7303b8a0626f1baded5c72a704f7e6cd84c OP_1 OP_CHECK_MULTISIG",
+		disassembly:    "010203040506070809 04ae1a62fe09c5f51b13905f07f06b99a2f7159b2225f374cd378d71302fa28414e7aab37397f554a7df5f142c21c1b7303b8a0626f1baded5c72a704f7e6cd84c OP_1 OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 1,
 	},
 	{
-		name: "OP_CHECK_MULTISIG too few sigs",
+		name: "OP_CHECKMULTISIG too few sigs",
 		script: []byte{btcscript.OP_1,
 			btcscript.OP_DATA_65,
 			0x04, 0xae, 0x1a, 0x62, 0xfe, 0x09, 0xc5, 0xf5, 0x1b,
@@ -2252,15 +2252,15 @@ var detailedTests = []detailedTest{
 			0xba, 0xde, 0xd5, 0xc7, 0x2a, 0x70, 0x4f, 0x7e, 0x6c,
 			0xd8, 0x4c,
 			btcscript.OP_1,
-			btcscript.OP_CHECK_MULTISIG},
+			btcscript.OP_CHECKMULTISIG},
 		expectedReturn: btcscript.StackErrUnderflow,
-		disassembly:    "OP_1 04ae1a62fe09c5f51b13905f07f06b99a2f7159b2225f374cd378d71302fa28414e7aab37397f554a7df5f142c21c1b7303b8a0626f1baded5c72a704f7e6cd84c OP_1 OP_CHECK_MULTISIG",
+		disassembly:    "OP_1 04ae1a62fe09c5f51b13905f07f06b99a2f7159b2225f374cd378d71302fa28414e7aab37397f554a7df5f142c21c1b7303b8a0626f1baded5c72a704f7e6cd84c OP_1 OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 1,
 	},
 	{
 		// pubkey and sig comes from blockchain, are unrelated
-		name: "OP_CHECK_MULTISIG won't verify",
+		name: "OP_CHECKMULTISIG won't verify",
 		script: []byte{btcscript.OP_1,
 			btcscript.OP_DATA_71,
 			0x30, 0x44, 0x02, 0x20, 0x4e, 0x45, 0xe1, 0x69, 0x32,
@@ -2282,9 +2282,9 @@ var detailedTests = []detailedTest{
 			0xba, 0xde, 0xd5, 0xc7, 0x2a, 0x70, 0x4f, 0x7e, 0x6c,
 			0xd8, 0x4c,
 			btcscript.OP_1,
-			btcscript.OP_CHECK_MULTISIG},
+			btcscript.OP_CHECKMULTISIG},
 		after:          [][]byte{{0}},
-		disassembly:    "OP_1 304402204e45e16932b8af514961a1d3a1a25fdf3f4f7732e9d624c6c61548ab5fb8cd410220181522ec8eca07de4860a4acdd12909d831cc56cbbac4622082221a8768d1d0901 OP_1 04ae1a62fe09c5f51b13905f07f06b99a2f7159b2225f374cd378d71302fa28414e7aab37397f554a7df5f142c21c1b7303b8a0626f1baded5c72a704f7e6cd84c OP_1 OP_CHECK_MULTISIG",
+		disassembly:    "OP_1 304402204e45e16932b8af514961a1d3a1a25fdf3f4f7732e9d624c6c61548ab5fb8cd410220181522ec8eca07de4860a4acdd12909d831cc56cbbac4622082221a8768d1d0901 OP_1 04ae1a62fe09c5f51b13905f07f06b99a2f7159b2225f374cd378d71302fa28414e7aab37397f554a7df5f142c21c1b7303b8a0626f1baded5c72a704f7e6cd84c OP_1 OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 1,
 	},
@@ -2292,7 +2292,7 @@ var detailedTests = []detailedTest{
 		// invalid pubkey means that it fails to validate, not an
 		// error.  There are pubkeys in the blockchain that don't
 		// parse with any validity.
-		name: "OP_CHECK_MULTISIG sigs bad pubkey",
+		name: "OP_CHECKMULTISIG sigs bad pubkey",
 		script: []byte{btcscript.OP_1,
 			btcscript.OP_DATA_71,
 			0x30, 0x44, 0x02, 0x20, 0x4e, 0x45, 0xe1, 0x69, 0x32,
@@ -2305,9 +2305,9 @@ var detailedTests = []detailedTest{
 			0x22, 0x21, 0xa8, 0x76, 0x8d, 0x1d, 0x09, 0x01,
 			btcscript.OP_1,
 			btcscript.OP_1, btcscript.OP_1,
-			btcscript.OP_CHECK_MULTISIG},
+			btcscript.OP_CHECKMULTISIG},
 		after:          [][]byte{{0}},
-		disassembly:    "OP_1 304402204e45e16932b8af514961a1d3a1a25fdf3f4f7732e9d624c6c61548ab5fb8cd410220181522ec8eca07de4860a4acdd12909d831cc56cbbac4622082221a8768d1d0901 OP_1 OP_1 OP_1 OP_CHECK_MULTISIG",
+		disassembly:    "OP_1 304402204e45e16932b8af514961a1d3a1a25fdf3f4f7732e9d624c6c61548ab5fb8cd410220181522ec8eca07de4860a4acdd12909d831cc56cbbac4622082221a8768d1d0901 OP_1 OP_1 OP_1 OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 1,
 	},
@@ -3090,10 +3090,10 @@ var detailedTests = []detailedTest{
 			btcscript.OP_1,
 			btcscript.OP_1,
 			btcscript.OP_2,
-			btcscript.OP_CHECK_MULTISIG,
+			btcscript.OP_CHECKMULTISIG,
 		},
 		expectedReturn: btcscript.StackErrTooManyOperations,
-		disassembly:    "OP_1 OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_1 OP_1 OP_1 OP_1 OP_2 OP_CHECK_MULTISIG",
+		disassembly:    "OP_1 OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_DUP OP_DROP OP_1 OP_1 OP_1 OP_1 OP_2 OP_CHECKMULTISIG",
 		nSigOps:        20,
 		nPreciseSigOps: 2,
 	},
diff --git a/script.go b/script.go
index 87b0867c..20f0ac30 100644
--- a/script.go
+++ b/script.go
@@ -237,7 +237,7 @@ func IsPayToScriptHash(script []byte) bool {
 func isMultiSig(pops []parsedOpcode) bool {
 	l := len(pops)
 	// absolute minimum is 1 pubkey so
-	// OP_1-16, pubkey, OP_1, OP_CHECK_MULTISIG
+	// OP_1-16, pubkey, OP_1, OP_CHECKMULTISIG
 	if l < 4 {
 		return false
 	}
@@ -249,7 +249,7 @@ func isMultiSig(pops []parsedOpcode) bool {
 		pops[l-2].opcode.value > OP_16 {
 		return false
 	}
-	if pops[l-1].opcode.value != OP_CHECK_MULTISIG {
+	if pops[l-1].opcode.value != OP_CHECKMULTISIG {
 		return false
 	}
 	for _, pop := range pops[1 : l-2] {
@@ -936,7 +936,7 @@ func getSigOpCount(pops []parsedOpcode, precise bool) int {
 			fallthrough
 		case OP_CHECKSIGVERIFY:
 			nSigs++
-		case OP_CHECK_MULTISIG:
+		case OP_CHECKMULTISIG:
 			fallthrough
 		case OP_CHECKMULTISIGVERIFY:
 			// If we are being precise then look for familiar
diff --git a/script_test.go b/script_test.go
index 690c15f1..c98bb188 100644
--- a/script_test.go
+++ b/script_test.go
@@ -958,7 +958,7 @@ var txTests = []txTest{
 						0x78, 0x86, 0x21, 0x1a, 0xb4,
 						0x14, 0xd5, 0x5a,
 						btcscript.OP_TRUE,
-						btcscript.OP_CHECK_MULTISIG,
+						btcscript.OP_CHECKMULTISIG,
 					},
 					Sequence: 4294967295,
 				},
@@ -1081,7 +1081,7 @@ var txTests = []txTest{
 						0x78, 0x86, 0x21, 0x1a, 0xb4,
 						0x14, 0xd5, 0x5a,
 						btcscript.OP_TRUE,
-						btcscript.OP_CHECK_MULTISIG,
+						btcscript.OP_CHECKMULTISIG,
 					},
 					Sequence: 4294967295,
 				},
@@ -1711,7 +1711,7 @@ func TestScriptInfo(t *testing.T) {
 				0xa, 0xb, 0xc, 0xd, 0xe, 0xf, 0x10, 0x11, 0x12,
 				0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a,
 				0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21,
-				btcscript.OP_3, btcscript.OP_CHECK_MULTISIG,
+				btcscript.OP_3, btcscript.OP_CHECKMULTISIG,
 			},
 			bip16: true,
 			scriptInfo: btcscript.ScriptInfo{
@@ -1990,7 +1990,7 @@ var scriptTypeTests = []scriptTypeTest{
 			0x45, 0x32, 0x9a, 0x00, 0x35, 0x7b, 0x3a, 0x78, 0x86,
 			0x21, 0x1a, 0xb4, 0x14, 0xd5, 0x5a,
 			btcscript.OP_TRUE,
-			btcscript.OP_CHECK_MULTISIG,
+			btcscript.OP_CHECKMULTISIG,
 		},
 		scripttype: btcscript.MultiSigTy,
 	},
@@ -2091,7 +2091,7 @@ var scriptTypeTests = []scriptTypeTest{
 			0x45, 0x32, 0x9a, 0x00, 0x35, 0x7b, 0x3a, 0x78, 0x86,
 			0x21, 0x1a, 0xb4, 0x14, 0xd5, 0x5a,
 			btcscript.OP_TRUE,
-			btcscript.OP_CHECK_MULTISIG,
+			btcscript.OP_CHECKMULTISIG,
 		},
 		scripttype: btcscript.NonStandardTy,
 	},
@@ -2102,7 +2102,7 @@ var scriptTypeTests = []scriptTypeTest{
 			btcscript.OP_TRUE,
 			btcscript.OP_TRUE,
 			btcscript.OP_TRUE,
-			btcscript.OP_CHECK_MULTISIG,
+			btcscript.OP_CHECKMULTISIG,
 		},
 		scripttype: btcscript.NonStandardTy,
 	},
@@ -2122,7 +2122,7 @@ var scriptTypeTests = []scriptTypeTest{
 			0x45, 0x32, 0x9a, 0x00, 0x35, 0x7b, 0x3a, 0x78, 0x86,
 			0x21, 0x1a, 0xb4, 0x14, 0xd5, 0x5a,
 			// No number.
-			btcscript.OP_CHECK_MULTISIG,
+			btcscript.OP_CHECKMULTISIG,
 		},
 		scripttype: btcscript.NonStandardTy,
 	},
@@ -2146,7 +2146,7 @@ var scriptTypeTests = []scriptTypeTest{
 		// multisig but wrong length.
 		script: []byte{
 			btcscript.OP_TRUE,
-			btcscript.OP_CHECK_MULTISIG,
+			btcscript.OP_CHECKMULTISIG,
 		},
 		scripttype: btcscript.NonStandardTy,
 	},