adjective \ˈwēk\

Definition of weak

  1. 1 :  lacking strength: such asa :  deficient in physical vigor :  feeble, debilitatedb :  not able to sustain or exert much weight, pressure, or strainc :  not able to resist external force or withstand attackd :  easily upset or nauseated a weak stomach

  2. 2a :  mentally or intellectually deficientb :  not firmly decided :  vacillatingc :  resulting from or indicating lack of judgment or discernmentd :  not able to withstand temptation or persuasion the spirit is willing but the flesh is weak

  3. 3 :  not factually grounded or logically presented a weak argument

  4. 4a :  not able to function properly weak eyesb (1) :  lacking skill or proficiency tutoring for weaker students (2) :  indicative of a lack of skill or aptitude history was my weakest subjectc :  wanting in vigor of expression or effect a weak translation of the poem

  5. 5a :  deficient in the usual or required ingredients :  dilute weak coffeeb :  lacking normal intensity or potency a weak radio signal a weak strain of virus

  6. 6a :  not having or exerting authority or political power weak governmentb :  ineffective, impotent

  7. 7 :  of, relating to, or constituting a verb or verb conjugation that in English forms the past tense and past participle by adding the suffix -ed or -d or -t

  8. 8a :  bearing the minimal degree of stress occurring in the language a weak syllableb :  having little or no stress and obscured vowel sound 'd in he'd is the weak form of would

  9. 9 :  tending toward a lower price or value a weak market a weak dollar

  10. 10 :  ionizing only slightly in solution weak acids and bases



Examples of weak in a Sentence

  1. He has a weak throwing arm.

  2. The illness left her too weak to stand up.

  3. The child was born with weak lungs.

  4. The batter hit a weak ground ball.

  5. She uttered her reply in a weak voice.

  6. The door's hinge is weak.

Recent Examples of weak from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'weak.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of weak

Middle English weike, from Old Norse veikr; akin to Old English wīcan to yield, Greek eikein to give way, Sanskrit vijate he speeds, flees

Synonym Discussion of weak

weak, feeble, frail, fragile, infirm, decrepit mean not strong enough to endure strain, pressure, or strenuous effort. weak applies to deficiency or inferiority in strength or power of any sort. felt weak after the surgery feeble suggests extreme weakness inviting pity or contempt. a feeble attempt to walk frail implies delicacy and slightness of constitution or structure. a frail teenager unable to enjoy sports fragile suggests frailty and brittleness unable to resist rough usage. a reclusive poet too fragile for the rigors of this world infirm suggests instability, unsoundness, and insecurity due to old age or crippling illness. infirm residents requiring constant care decrepit implies being worn-out or broken-down from long use or old age. the dowager's decrepit retainers

WEAK Defined for English Language Learners



Definition of weak for English Language Learners

  • : having little physical power or ability : not strong

  • : having little power or force

  • : likely to break or stop working properly : not able to handle weight, pressure, or strain

WEAK Defined for Kids


adjective \ˈwēk\

Definition of weak for Students




  1. 1 :  lacking strength of body, mind, or spirit a weak smile a weak patient

  2. 2 :  not able to stand much strain or force a weak rope

  3. 3 :  easily overcome a weak argument

  4. 4 :  not able to function well a weak heart

  5. 5 :  not rich in some usual or important element weak tea

  6. 6 :  lacking experience or skill He's a good reader, but is weak in math.

  7. 7 :  not loud or forceful a weak voice

  8. 8 :  relating to or being the lightest of three levels of stress in pronunciation



Seen and Heard

What made you want to look up weak? Please tell us where you read or heard it (including the quote, if possible).

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!


to fight against or to call in question

Get Word of the Day daily email!

Test Your Vocabulary

Time Traveler Quiz: Which Word Came First?

  • time-traveler-quiz-which-word-came-first
  • Which came first?
True or False

Test your knowledge - and maybe learn something along the way.

Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!