Found 2 items, similar to knuckle under.
English → English (WordNet) Definition: knuckle under knuckle under v : consent reluctantly [syn: yield, give in, succumb, buckle under ]
English → English (gcide) Definition: knuckle under knuckle under \knuc`kle un"der\, v. i. To yield; to submit; -- usually used with to. [PJC]