Recently, the provenance of Asciz has become clear. Constant pool entry type 1 used to be CONSTANT_Asciz (or CONSTANT_Asciiz, depending where you read) and Constant pool entry type 2 used to be CONSTANT_Unicode. Both names date from around 1995 and JDK 1.0. By the time of JVMS 1st edition, constant pool entry types 1 and 2 had been combined into CONSTANT_Utf8, value 1, with 2 being unused.
The suggested name for all tag entries is the JVMS name, without the leading CONSTANT_