#1 stultify v. prove to be of unsound mind or demonstrate someone's incompetence; "nobody is legally allowed to stultify himself". wn
#2 stultify v. cause to appear foolish; "He stultified himself by contradicting himself and being inconsistent". wn
#3 stultify v. [cripple] deprive of strength or efficiency; make useless or worthless; "This measure crippled our efforts"; "Their behavior stultified the boss's hard work". wn
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