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adjective, \ə-ˈkyüt\

Simple Definition of acute

  • : very serious or dangerous : requiring serious attention or action

  • : having or showing an ability to think clearly and to understand what is not obvious or simple about something

  • : very strong and sensitive : highly developed

Source: Merriam-Webster's Learner's Dictionary

Full Definition of acute


  1. 1 a (1) :  characterized by sharpness or severity <acute pain> (2) :  having a sudden onset, sharp rise, and short course <acute disease> (3) :  being, providing, or requiring short-term medical care (as for serious illness or traumatic injury) <acute hospitals> <an acute patient> b :  lasting a short time <acute experiments>

  2. 2 :  ending in a sharp point: as a :  being or forming an angle measuring less than 90 degrees <an acute angle> b :  composed of acute angles <an acute triangle>

  3. 3 a of an accent mark :  having the form ´ b :  marked with an acute accent c :  of the variety indicated by an acute accent

  4. 4 a :  marked by keen discernment or intellectual perception especially of subtle distinctions <an acute thinker> b :  responsive to slight impressions or stimuli <acute hearing>

  5. 5 :  felt, perceived, or experienced intensely <acute distress>

  6. 6 :  demanding urgent attention <an acute emergency>

acutely adverb
acuteness noun

Examples of acute in a sentence

  1. an acute sense of humor

  2. It's a politically acute film that does not oversimplify the issues.

Ways to be acute

For such a short and simple-looking word, acute has a rather bewildering range of meanings. It first entered the English language with a medical sense, referring to the sharpness or severity of a symptom. It retains this meaning today, but can also refer to the severity of more general matters, such as "acute embarrassment" or "an acute shortage."

Acute is also frequently used to describe less troublesome matters, such as keenness of perception ("an acute observer" or "an acute sense of smell"), a type of angle (one measuring less than 90 degrees), or the demand for urgent attention ("acute danger").

Origin of acute

Middle English, from Latin acutus, past participle of acuere to sharpen, from acus needle; akin to Latin acer sharp — more at edge

First Known Use: 14th century

Synonym Discussion of acute

acute, critical, crucial mean of uncertain outcome. acute stresses intensification of conditions leading to a culmination or breaking point <an acute housing shortage>. critical adds to acute implications of imminent change, of attendant suspense, and of decisiveness in the outcome <the war has entered a critical phase>. crucial suggests a dividing of the ways and often a test or trial involving the determination of a future course or direction <a crucial vote>.

synonyms see in addition sharp

ACUTE Defined for Kids


adjective \ə-ˈkyüt\

Definition of acute for Students


  1. 1 :  measuring less than 90 degrees <acute angles>

  2. 2 :  marked by or showing an ability to understand things that are not obvious <an acute observation>

  3. 3 :  severe, sharp <acute pain>

  4. 4 :  developing quickly and lasting only a short time <acute illness>

  5. 5 :  critical 4, urgent <an acute shortage of food>

  6. 6 :  very strong and sensitive <an acute sense of smell>

acutely adverb
acuteness noun

Medical Dictionary


adjective \ə-ˈkyüt\

Medical Definition of acute

  1. 1:  sensing or perceiving accurately, clearly, effectively, or sensitively <acute vision>

  2. 2a:  characterized by sharpness or severity of sudden onset <acute pain brought on by injury> <an acute infection>b (1):  having a sudden onset, sharp rise, and short course <acute illness> <an acute inflammation>—compare chronic 2a (2):  acute care <an acute hospital>c:  lasting a short time <acute experiments>

acutely adverb
acuteness noun

Seen and Heard

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


tending to dismiss important matters

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