balls something up

Từ điển Oxford Advanced Learner 8th

ˌballs sthˈup derived
(BrE, taboo, slang)to spoil sth; to do sth very badly
related noun ↑balls-up  A more polite way of saying this is foul sth up, mess sth up, or bungle sth.
Main entry: ↑balls_derived