Poisoned cue
A word that has been followed by something unpleasant often enough that the dog now hesitates when it hears it.
Also called: ruined command · he ignores the word
Cues carry a history. If "come" has sometimes meant a bath, sometimes meant the end of the park and occasionally meant being shouted at, it no longer means come — it means something is about to happen and it might be bad.
The tell is a delay: the dog hears the word, pauses, sniffs something, then complies slowly. Owners read this as defiance. It is closer to dread.
Poisoned cues are usually cheaper to replace than to repair. Pick a new word, pay it properly, and retire the old one.