weaken

verb

1. lessen the strength of

   verb.change

   Examples

   The fever weakened his body.

   Antonyms beef up fortify strengthen

   Source: WordNet 3.0

2. become weaker

   verb.change

   Examples

   The prisoner's resistance weakened after seven days.

   Synonyms dissolve fade away fade out

   Antonyms strengthen

   Source: WordNet 3.0

3. destroy property or hinder normal operations

   verb.social

   Synonyms counteract countermine sabotage subvert undermine

   Source: WordNet 3.0

4. reduce the level or intensity or size or scope of

   verb.change

   Synonyms de-escalate step down

   Antonyms escalate intensify step up

   Source: WordNet 3.0

5. lessen in force or effect

   verb.change

   Synonyms break damp dampen soften

   Source: WordNet 3.0

6. To make weak; to lessen the strength of; to deprive of strength; to debilitate; to enfeeble; to enervate; as, to <i>weaken</i> the body or the mind; to <i>weaken</i> the hands of a magistrate; to <i>weaken</i> the force of an objection or an argument.

   verb

   Source: webster1913

7. To become weak or weaker; to lose strength, spirit, or determination; to become less positive or resolute; as, the patient <i>weakened</i>; the witness <i>weakened</i> on cross-examination.

   verb

   Source: webster1913