knuckle under

1 to cease resistance (as to another's arguments, demands, or control) encouraged her to stand firm and not knuckle under to political pressure Synonyms blink, bow, budge, capitulate, concede, give in, yield, quit, relent, submit, succumb, surrenderRelated Words acquiesce; deferNear Antonyms contend, fight, hold off; battle, breast, combat, confront, counter, defy, face, meet, object, oppose, repel; thwart, withstandAntonyms resist

2 to yield to the control or power of enemy forces the remote outpost was overrun and forced to knuckle under Synonyms capitulate, give up, fall, submit, succumb, surrenderRelated Words bow, buckle, cave (in), collapse, give (in); hand over, relinquish; lose; concede, fail, foldNear Antonyms buck, defy, fight, oppose, repel, resist, withstand; beat, overcome, win; conquer, prevail, triumphAntonyms endure, stand