lacking the power to perform physically demanding tasks; having little physical strength or energy

she was recovering from flu, and was very weak

liable to break or give way under pressure; easily damaged

the salamander's tail may be broken off at a weak spot near the base

lacking intensity or brightness

a weak light from a single street lamp

denoting a class of verbs in Germanic languages that form the past tense and past participle by addition of a suffix (in English, typically -ed)

relating to or denoting the weakest of the known kinds of force between particles, which acts only at distances less than about 10? cm, is very much weaker than the electromagnetic and the strong interactions, and conserves neither strangeness, parity, nor isospin