<p><strong>Adjective</strong></p><ul><li>not strong;</li><li>liable to yield, break, or collapse under pressure or strain;</li><li>fragile;</li><li>frail: a weak fortress;</li><li>a weak spot in armor.</li><li>Synonyms: breakable, delicate.</li><li>Antonyms: strong.</li><li>lacking in bodily strength or healthy vigor, as from age or sickness;</li><li>feeble;</li><li>infirm: a weak old man;</li><li>weak eyes.</li><li>Synonyms: invalid, unwell, sickly, senile.</li><li>not having much political strength, governing power, or authority: a weak nation; a weak ruler.</li><li>lacking in force, potency, or efficacy; impotent, ineffectual, or inadequate: weak sunlight; a weak wind.</li><li>Synonyms: ineffective.</li><li>lacking in rhetorical or creative force or effectiveness: a weak reply to the charges; one of the author's weakest novels.</li><li>lacking in logical or legal force or soundness: a weak argument.</li><li>Synonyms: vague, lame, unsatisfactory, inconclusive, illogical, inadequate, ineffective, unsound.</li><li>deficient in mental power, intelligence, or judgment: a weak mind.</li><li>Synonyms: stupid, foolish, simple, unintelligent, silly, senseless.</li><li>not having much moral strength or firmness, resolution, or force of character: to prove weak under temptation; weak compliance.</li><li>Synonyms: weak-kneed, undecided, irresolute, unstable, vacillating.</li><li>deficient in amount, volume, loudness, intensity, etc.; faint; slight: a weak current of electricity; a weak pulse.</li><li>Synonyms: trivial, trifling, poor, flimsy, inconsiderable, slim, slender.</li><li>deficient, lacking, or poor in something specified: a hand weak in trumps; I'm weak in spelling.</li><li>deficient in the essential or usual properties or ingredients: weak tea.</li><li>Synonyms: lacking, short, wanting.</li><li>unstressed, as a syllable, vowel, or word.</li><li>(of Germanic verbs) inflected with suffixes, without inherited change of the root vowel, as English work, worked, or having a preterit ending in a dental, as English bring, brought.</li><li>(of Germanic nouns and adjectives) inflected with endings originally appropriate to stems terminating in -n, as the adjective alte in German der alte Mann (“the old man”).</li><li>(of wheat or flour) having a low gluten content or having a poor quality of gluten.</li><li>Photography: thin; not dense.</li><li>Commerce: characterized by a decline in prices: The market was weak in the morning but rallied in the afternoon.</li></ul>