prevent

Synonyms: anticipate arrest avert avoid baffle balk bar block check chill cool cork counter counteract dam debar defend against foil forbid forestall forfend frustrate halt hamper head off hinder hold back hold off impede inhibit intercept interdict interrupt keep lid on limit nip in the bud obstruct obviate preclude prohibit put an end to put a stop to repress restrain restrict retard rule out shut out stave off stop thwart turn aside ward off

Antonyms: aid allow assist cause help let go