#1 thwart v. [queer, spoil, scotch, foil, cross, frustrate, baffle, bilk] hinder or prevent (the efforts, plans, or desires) of; "What ultimately frustrated every challenger was Ruth's amazing September surge"; "foil your opponent". wn
#2 thwart n. [cross thwart] a crosspiece spreading the gunnels of a boat; used as a seat in a rowboat. wn
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