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definitions

excuse

[verb ik-skyooz; noun ik-skyoos]
verb (used with object), ex·cused, ex·cus·ing.
  1. to regard or judge with forgiveness or indulgence; pardon or forgive; overlook (a fault, error, etc.): Excuse his bad manners.
  2. to offer an apology for; seek to remove the blame of: He excused his absence by saying that he was ill.
  3. to serve as an apology or justification for; justify: Ignorance of the law excuses no one.
  4. to release from an obligation or duty: to be excused from jury duty.
  5. to seek or obtain exemption or release for (oneself): to excuse oneself from a meeting.
  6. to refrain from exacting; remit; dispense with: to excuse a debt.
  7. to allow (someone) to leave: If you'll excuse me, I have to make a telephone call.
noun
  1. an explanation offered as a reason for being excused; a plea offered in extenuation of a fault or for release from an obligation, promise, etc.: His excuse for being late was unacceptable.
  2. a ground or reason for excusing or being excused: Ignorance is no excuse.
  3. the act of excusing someone or something.
  4. a pretext or subterfuge: He uses his poor health as an excuse for evading all responsibility.
  5. an inferior or inadequate specimen of something specified: That coward is barely an excuse for a man. Her latest effort is a poor excuse for a novel.
Idioms
  1. Excuse me, (used as a polite expression, as when addressing a stranger, when interrupting or disagreeing with someone, or to request repetition of what has just been said.)

Origin of excuse

1175–1225; (v.) Middle English escusen < Old French escuser < Latin excūsāre to put outside, exonerate, equivalent to ex- ex-1 + -cūsāre, derivative of causa cause; (noun) Middle English escuse < Old French, derivative of escuser; modern spelling with ex- on the model of ex-1
Related formsex·cus·a·ble, adjectiveex·cus·a·ble·ness, nounex·cus·a·bly, adverbex·cus·al, nounex·cuse·less, adjectiveex·cus·er, nounex·cus·ing·ly, adverbex·cus·ive, adjectiveex·cus·ive·ly, adverbnon·ex·cus·a·ble, adjectivenon·ex·cus·a·ble·ness, nounnon·ex·cus·a·bly, adverbpre·ex·cuse, verb (used with object), pre·ex·cused, pre·ex·cus·ing.self-ex·cuse, nounself-ex·cused, adjectiveself-ex·cus·ing, adjectiveun·ex·cus·a·ble, adjectiveun·ex·cus·a·bly, adverbun·ex·cused, adjectiveun·ex·cus·ing, adjective
Can be confusedalibi excuse (see usage note at alibi) (see synonym study at the current entry)

Synonyms for excuse

1. Excuse, forgive, pardon imply being lenient or giving up the wish to punish. Excuse means to overlook some (usually) slight offense: to excuse bad manners. Forgive is applied to excusing more serious offenses: to forgive and forget. Pardon usually applies to a specific act of lenience or mercy by an official or superior: The governor was asked to pardon the condemned criminal. 3. extenuate, palliate. 4. free. 8. justification. Excuse, apology both imply an explanation of some failure or failing. Excuse implies a desire to avoid punishment or rebuke. Apology usually implies acknowledgment that one has been in the wrong. 11. pretense, evasion, makeshift.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for unexcusable

Historical Examples of unexcusable

British Dictionary definitions for unexcusable

excuse

verb (ɪkˈskjuːz) (tr)
  1. to pardon or forgivehe always excuses her unpunctuality
  2. to seek pardon or exemption for (a person, esp oneself)to excuse oneself for one's mistakes
  3. to make allowances for; judge lenientlyto excuse someone's ignorance
  4. to serve as an apology or explanation for; vindicate or justifyher age excuses her behaviour
  5. to exempt from a task, obligation, etcyou are excused making breakfast
  6. to dismiss or allow to leavehe asked them to excuse him
  7. to seek permission for (someone, esp oneself) to leavehe excused himself and left
  8. be excused euphemistic to go to the lavatory
  9. excuse me! an expression used to catch someone's attention or to apologize for an interruption, disagreement, or social indiscretion
noun (ɪkˈskjuːs)
  1. an explanation offered in defence of some fault or offensive behaviour or as a reason for not fulfilling an obligation, etche gave no excuse for his rudeness
  2. informal an inferior example of something specified; makeshift; substituteshe is a poor excuse for a hostess
  3. the act of excusing
Derived Formsexcusable, adjectiveexcusableness, nounexcusably, adverb

Word Origin for excuse

C13: from Latin excusāre, from ex- 1 + -cūsare, from causa cause, accusation
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for unexcusable
adj.

late 14c., from un- (1) "not" + excusable. The usual word is inexcusable. Related: Unexcusably.

excuse

v.

early 13c., "attempt to clear (someone) from blame," from Old French escuser (12c., Modern French excuser) "apologize, make excuses; pardon, exonerate," from Latin excusare "excuse, make an excuse for, release from a charge," from ex- "out, away" (see ex-) + causa "accusation, legal action" (see cause).

Meaning "to obtain exemption or release" is from mid-15c.; that of "to accept another's plea of excuse" is from early 14c. Excuse me as a mild apology or statement of polite disagreement is from c.1600.

excuse

n.

late 14c., "action of offering an apology," from Old French excuse, from excuser (see excuse (v.)). The sense of "that serves as a reason for being excused" is recorded from late 15c.

Online Etymology Dictionary, © 2010 Douglas Harper