tr.v. thwart·ed, thwart·ing, thwarts 1. To prevent the occurrence, realization, or attainment of: They thwarted her plans. 2. To oppose and defeat the efforts, plans, or ambitions of (someone).

to prevent someone from doing what they want to do synonym frustrate thwart something to thwart someone's plans thwart somebody (in something) She was thwarted in her attempt to take control of the party.

From Longman Dictionary of Contemporary English thwart /θwɔːt $ θwɔːrt/ ●○○ verb [transitive] formal to prevent someone from doing what they are trying to do Fierce opposition thwarted the government’s plans. thwarted ambition → See Verb table Examples from the Corpus thwart • This revolution, how-ever, was thwarted almost at once.