- 1[transitive, intransitive] weaken (somebody/something) to make someone or something less strong or powerful; to become less strong or powerful The team has been weakened by injury. The new evidence weakens the case against her. This new story has severely weakened the president's position. His authority is steadily weakening. opposite strengthen
- 2[transitive, intransitive] weaken (somebody/something) to make someone or something physically less strong; to become physically less strong The explosion had weakened the building's foundations. His health was weakened by overwork. She felt her legs weaken.
- 3[intransitive, transitive] to become or make someone become less determined or certain about something You must not agree to do it. Don't weaken. weaken something Nothing could weaken his resolve to continue.
NAmE//ˈwikən//Verb Forms present simple I / you / we / they weaken
he / she / it weakens
past simple weakened
-ing form weakening