Wiktionary
n. (context linguistics English) An overreaching or contradictory combination of two distinct metaphors, similes or idioms.
WordNet
n. a combination of two or more metaphors that together produce a ridiculous effect
Usage examples of "mixed metaphor".
A mixed metaphor that Sanchez, who had some pretensions to poetry, would wince at.
Afterwards he took us to a distant meadow, and there in the shade of a tree we listened to an old-fashioned speech from him, full of gunpowder and glory, full of that adjective-piling, mixed metaphor, and windy declamation which was regarded as eloquence in that ancient time and that remote region.
The blind, imperialist monster who moved down and snuffed out (mixed metaphor) human aspiration, the calculations of the still extant anti-Party group in eastern United States.
By all they've said, experienced aircrew are getting rather thin on the ground, if you'll forgive something of a mixed metaphor.
Told by superior to subordinate, handed down by word of mouth, if you don't object to an abs-urd mixed metaphor.