#1 frustrate v. [thwart, queer, spoil, scotch, foil, cross, 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 frustrate v. [torment, rag, bedevil, crucify, dun] treat cruelly; "The children tormented the stuttering teacher". wn
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