weak

UK: /ˈwiːk/ US: /wik/ ,(wēk)

Inflections of 'weak' (adj):

weaker

adj comparative

weakest

adj superlative

WordReference Random House Learner's Dictionary of American English © 2026

weak /wik/   adj., -er, -est. 

1. liable to give way under pressure or strain:
   The walls are too weak to support the house.
2. lacking in strength or vigor;
   feeble:
   He's weak from hunger.
3. lacking in force, intensity, or ability to produce an effect:
   a weak president.
4. lacking in logical or legal force:
   a weak argument.
5. low in intelligence, ability, or skill:
   a weak mind; a weak speller.
6. lacking in moral strength or force of character:
   too weak to resist temptation.
7. not great in amount, volume, intensity, etc., or in a characteristic property or essential ingredient:
   a weak electrical current; a weak pulse.
8. Business showing a decline in prices:
   a weak stock market.

weak•ly, adv. 

WordReference Random House Unabridged Dictionary of American English © 2026

weak  (wēk), adj., -er, -est. 

1. not strong;
   liable to yield, break, or collapse under pressure or strain;
   fragile;
   frail:
   a weak fortress; a weak spot in armor.
2. lacking in bodily strength or healthy vigor, as from age or sickness;
   feeble;
   infirm:
   a weak old man; weak eyes.
3. not having much political strength, governing power, or authority:
   a weak nation; a weak ruler.
4. lacking in force, potency, or efficacy;
   impotent, ineffectual, or inadequate:
   weak sunlight; a weak wind.
5. lacking in rhetorical or creative force or effectiveness:
   a weak reply to the charges; one of the author's weakest novels.
6. lacking in logical or legal force or soundness:
   a weak argument.
7. deficient in mental power, intelligence, or judgment:
   a weak mind.
8. not having much moral strength or firmness, resolution, or force of character:
   to prove weak under temptation; weak compliance.
9. deficient in amount, volume, loudness, intensity, etc.;
   faint;
   slight:
   a weak current of electricity; a weak pulse.
10. deficient, lacking, or poor in something specified:
    a hand weak in trumps; I'm weak in spelling.
11. deficient in the essential or usual properties or ingredients:
    weak tea.
12. Phonetics unstressed, as a syllable, vowel, or word.
13. Grammar (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.
14. Grammar (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'').
15. Nutrition (of wheat or flour) having a low gluten content or having a poor quality of gluten.
16. Photography thin;
    not dense.
17. Business [Com.] characterized by a decline in prices:
    The market was weak in the morning but rallied in the afternoon.

• Old Norse veikr; cognate with Old English wāc, Dutch week, German weich; akin to Old English wīcan to yield, give way, Old Norse vīkja to move, turn, draw back, German weichen to yield
• Middle English weik 1250–1300

Synonyms

• 1. breakable, delicate.
• 2. senile, sickly, unwell, invalid.
  Weak, decrepit, feeble, weakly imply a lack of strength or of good health.
  Weak means not physically strong, because of extreme youth, old age, illness, etc.:
  weak after an attack of fever.
  Decrepit means old and broken in health to a marked degree:
  decrepit and barely able to walk.
  Feeble denotes much the same as weak, but connotes being pitiable or inferior:
  feeble and almost senile.
  Weakly suggests a long-standing sickly condition, a state of chronic bad health:
  A weakly child may become a strong adult.
• 4. ineffective.
• 6. unsound, ineffective, inadequate, illogical, inconclusive, unsustained, unsatisfactory, lame, vague.
• 7. unintelligent, simple, foolish, stupid, senseless, silly.
• 8. vacillating, wavering, unstable, irresolute, fluctuating, undecided, weak-kneed.
• 9. slender, slim, inconsiderable, flimsy, poor, trifling, trivial.
• 11. wanting, short, lacking.

Antonyms

• 1. strong.

Collins Concise English Dictionary © HarperCollins Publishers::

weak / wiːk/ adjective

1. lacking in physical or mental strength or force; frail or feeble
2. liable to yield, break, or give way: a weak link in a chain
3. lacking in resolution or firmness of character
4. lacking strength, power, or intensity: a weak voice
5. lacking strength in a particular part: a team weak in defence
6. not functioning as well as normal: weak eyes
7. easily upset: a weak stomach
8. lacking in conviction, persuasiveness, etc: a weak argument
9. lacking in political or strategic strength: a weak state
10. lacking the usual, full, or desirable strength of flavour: weak tea
11. denoting or belonging to a class of verbs, in certain languages including the Germanic languages, whose conjugation relies on inflectional endings rather than internal vowel gradation, as look, looks, looking, looked
12. belonging to any part-of-speech class, in any of various languages, whose inflections follow the more regular of two possible patterns
    Compare strong13
13. (of a syllable) not accented or stressed
14. (of a fuel-air mixture) containing a relatively low proportion of fuel
    Compare rich13
15. (of an industry, market, currency, securities, etc) falling in price or characterized by falling prices

Etymology: Old English wāc soft, miserable; related to Old Saxon wēk, Old High German weih, Old Norse veikr

ˈweakish adjective