What is Thwart ?
Thwart is (verb) to prevent someone doing something He was thwarted by the police in his attempt to get into the building. His career move was thwarted by the new manager. Synonym frustrate. Antonym aid (noun) a seat across a rowing boat, for a rower to sit on They sat side-by-side on the thwart and each took an oar.
source: Easier English, Student Dictionary Upper Intermediate Level