Definition from Wiktionary, the free dictionary
- (slang, derogatory, idiomatic) One who lacks guts or courage; a coward.
1993, Archie Weller, Going Home:
- Yer can't even fight unless you've got a knife or picket or broken bottle, yer gutless wonder.
The idea is that the addressee's figurative gutlessness (cowardice) has been carried over into physical gutlessness (disembowelment), and that his bowel-less survival is a wonder.
- See also Wikisaurus:coward