prevent
prevent (prĭ-vĕntʹ) verb
prevented, preventing, prevents
verb, transitive
1. To keep from happening: took steps to prevent the strike.
2. To keep (someone) from doing something; impede: prevented us from winning.
3. Archaic. To anticipate or counter in advance.
4. Archaic. To come before; precede.
verb, intransitive
To present an obstacle: There will be a picnic if nothing prevents.
[Middle English preventen, to anticipate, from Latin praevenīre, praevent- : prae-, pre- + venīre, to come.]
preventabilʹity or preventibilʹity noun
preventʹable or preventʹible adjective
preventʹer noun
Synonyms: prevent, preclude, avert, obviate, forestall. These verbs mean to stop or hinder something from happening, especially by advance planning or action. Prevent implies anticipatory counteraction: "The surest way to prevent war is not to fear it" (John Randolph). To preclude is to exclude the possibility of the occurrence of an event or action: "a tranquillity which . . . his wife's presence would have precluded" (John Henry Newman). To avert is to ward off something about to happen: Only quick thinking on the pilot's part averted a disastrous accident. Obviate implies that something, such as a difficulty, has been anticipated and disposed of effectively: "the objections . . . having . . . been obviated in the preceding chapter" (Joseph Butler). Forestall usually suggests anticipatory measures taken to counteract, neutralize, or nullify the effects of something: We installed an alarm system to forestall break-ins.