diff --git a/readme.md b/readme.md
index 03e9cbe..50d6c28 100644
--- a/readme.md
+++ b/readme.md
@@ -311,6 +311,7 @@
 * **XBYAK64_GCC** is defined on 64bit gcc, cygwin
 * define **XBYAK_NO_OP_NAMES** on gcc without `-fno-operator-names`
 * define **XBYAK_ENABLE_OMITTED_OPERAND** if you use omitted destination such as `vaddps(xmm2, xmm3);`(duplicated in the future)
+* define **XBYAK_UNDEF_JNL** if Bessel function jnl is defined as macro
 
 Sample
 -------------
diff --git a/xbyak/xbyak.h b/xbyak/xbyak.h
index ba7e48d..08ea7e6 100644
--- a/xbyak/xbyak.h
+++ b/xbyak/xbyak.h
@@ -2372,6 +2372,9 @@
 	}
 #endif
 
+#ifdef XBYAK_UNDEF_JNL
+	#undef jnl
+#endif
 #ifndef XBYAK_DONT_READ_LIST
 #include "xbyak_mnemonic.h"
 	void align(int x = 16)