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?¹⁵ cm, is very much weaker than the electromagnetic and the strong interactions, and conserves neither strangeness, parity, nor isospin