lacking the power to perform physically demanding tasks; lacking physical strength and energy.
she was recovering from the 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 ); contrasted with strong.
Some phrasal verbs prefer a weak form (contrast The car sped up the hill and The car speeded up).
of, 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.
Thus, the strengths of the electromagnetic, weak , and strong forces depend upon the energy at which they are measured.