What does "weak" mean?

Weak: Not possessing or manifesting intellectual, logical, moral, or political strength, vigor, etc. Specifically: - (a) Feeble of mind; wanting discernment; lacking vigor; spiritless; as, a weak king or magistrate. To think every thing disputable is a proof of a weak mind and captious temper. Beattie. Origen was never weak enough to imagine that there were two Gods. Waterland. (b) Resulting from, or indicating, lack of judgment, discernment, or firmness; unwise; hence, foolish. If evil thence ensue, She first his weak indulgence will accuse. Milton. (c) Not having full confidence or conviction; not decided or confirmed; vacillating; wavering. Him that is weak in the faith receive ye, but not to doubtful disputations. Rom. xiv.

Additional senses

  1. 2.(d) Not able to withstand temptation, urgency, persuasion, etc.; easily impressed, moved, or overcome; accessible; vulnerable; as, weak resolutions; weak virtue. Guard thy heart On this weak side, where most our nature fails. Addison. (e) Wanting in power to influence or bind; as, weak ties; a weak sense of honor of duty. (f) Not having power to convince; not supported by force of reason or truth; unsustained; as, a weak argument or case. "Convinced of his weak arguing." Milton. A case so weak . . . hath much persisted in. Hooker. (g) Wanting in point or vigor of expression; as, a weak sentence; a weak style. (h) Not prevalent or effective, or not felt to be prevalent; not potent; feeble. "Weak prayers." Shak. (i) Lacking in elements of political strength; not wielding or having authority or energy; deficient in the resources that are essential to a ruler or nation; as, a weak monarch; a weak government or state. I must make fair weather yet awhile, Till Henry be more weak, and I more strong. Shak. (k) (Stock Exchange) Tending towards lower prices; as, a weak market.
  2. 3.(Gram.) (a) Pertaining to, or designating, a verb which forms its preterit (imperfect) and past participle by adding to the present the suffix - ed, -d, or the variant form -t; as in the verbs abash, abashed; abate, abated; deny, denied; feel, felt. See Strong, 19 (a). (b) Pertaining to, or designating, a noun in Anglo-Saxon, etc., the stem of which ends in -n. See Strong, 19 (b). Note: Weak is often used in the formation of self-explaining compounds; as, weak-eyed, weak-handed, weak-hearted, weak-minded, weak-spirited, and the like. Weak conjugation (Gram.), the conjugation of weak verbs; -- called also new, or regular, conjugation, and distinguished from the old, or irregular, conjugation. -- Weak declension (Anglo-Saxon Gram.), the declension of weak nouns; also, one of the declensions of adjectives. -- Weak side, the side or aspect of a person's character or disposition by which he is most easily affected or influenced; weakness; infirmity. -- Weak sore or ulcer (Med.), a sore covered with pale, flabby, sluggish granulations.
  3. 4.To make or become weak; to weaken. [R.] Never to seek weaking variety. Marston.

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