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definitions

reason

[ree-zuhn]
See more synonyms for reason on Thesaurus.com
noun
  1. a basis or cause, as for some belief, action, fact, event, etc.: the reason for declaring war.
  2. a statement presented in justification or explanation of a belief or action: I dare you to give me one good reason for quitting school!
  3. the mental powers concerned with forming conclusions, judgments, or inferences: Effective leadership requires a person of reason.
  4. sound judgment; good sense.
  5. normal or sound powers of mind; sanity.
  6. Logic. a premise of an argument.
  7. Philosophy.
    1. the faculty or power of acquiring intellectual knowledge, either by direct understanding of first principles or by argument.
    2. the power of intelligent and dispassionate thought, or of conduct influenced by such thought.
    3. Kantianism.the faculty by which the ideas of pure reason are created.
verb (used without object)
  1. to think or argue in a logical manner.
  2. to form conclusions, judgments, or inferences from facts or premises.
  3. to urge reasons which should determine belief or action.
verb (used with object)
  1. to think through logically, as a problem (often followed by out).
  2. to conclude or infer.
  3. to convince, persuade, etc., by reasoning.
  4. to support with reasons.
Idioms
  1. bring (someone) to reason, to induce a change of opinion in (someone) through presentation of arguments; convince: The mother tried to bring her rebellious daughter to reason.
  2. by reason of, on account of; because of: He was consulted about the problem by reason of his long experience.
  3. in/within reason, in accord with reason; justifiable; proper: She tried to keep her demands in reason.
  4. stand to reason, to be clear, obvious, or logical: With such an upbringing it stands to reason that the child will be spoiled.
  5. with reason, with justification; properly: The government is concerned about the latest crisis, and with reason.

Origin of reason

1175–1225; Middle English resoun, reisun (noun) < Old French reisun, reson < Latin ratiōn- (stem of ratiō) ratio
Related formsrea·son·er, nounnon·rea·son, nounnon·rea·son·er, nounout·rea·son, verb (used with object)sub·rea·son, noun

Synonyms for reason

See more synonyms for on Thesaurus.com
1. purpose, end, aim, object, objective. 2. excuse, rationalization. 3. understanding, intellect, mind, intelligence. 10. persuade.

Synonym study

1. Reason, cause, motive are terms for a circumstance (or circumstances) which brings about or explains certain results. A reason is an explanation of a situation or circumstance which made certain results seem possible or appropriate: The reason for the robbery was the victim's display of his money. The cause is the way in which the circumstances produce the effect, that is, make a specific action seem necessary or desirable: The cause was the robber's extreme need of money. A motive is the hope, desire, or other force which starts the action (or an action) in an attempt to produce specific results: The motive was to get money to buy food for his family.

Usage note

The construction reason is because is criticized in a number of usage guides: The reason for the long delays was because the costs greatly exceeded the original estimates. One objection to this construction is based on its redundancy: the word because (literally, by cause ) contains within it the meaning of reason; thus saying the reason is because is like saying “The cause is by cause,” which would never be said. A second objection is based on the claim that because can introduce only adverbial clauses and that reason is requires completion by a noun clause. Critics would substitute that for because in the offending construction: The reason for the long delays in completing the project was that the costs. … Although the objections described here are frequently raised, reason is because is still common in almost all levels of speech and occurs often in edited writing as well.
A similar charge of redundancy is made against the reason why, which is also a well-established idiom: The reason why the bill failed to pass was the defection of three key senators.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for reason

logic, reasoning, sense, motivation, goal, basis, idea, incentive, argument, motive, impetus, purpose, rationale, consideration, cause, proof, case, justification, excuse, speculate

Examples from the Web for reason

Contemporary Examples of reason

Historical Examples of reason

  • There was no time barren enough of sensation to reason about it.

    The Spenders

    Harry Leon Wilson

  • I think this blessing comes from the Divine, by reason of the innocence of his life.

    Philothea

    Lydia Maria Child

  • I haven't told you yet the reason—a new reason—why you must talk to Avice.

    The Spenders

    Harry Leon Wilson

  • The reason I write promptly is that you may not go out of the country just now.

    The Spenders

    Harry Leon Wilson

  • That he had reason for his distrust was proved by Ben Haley's movements.

    Brave and Bold

    Horatio Alger

British Dictionary definitions for reason

reason

noun
  1. the faculty of rational argument, deduction, judgment, etc
  2. sound mind; sanity
  3. a cause or motive, as for a belief, action, etc
  4. an argument in favour of or a justification for something
  5. philosophy the intellect regarded as a source of knowledge, as contrasted with experience
  6. logic grounds for a belief; a premise of an argument supporting that belief
  7. by reason of because of
  8. in reason or within reason within moderate or justifiable bounds
  9. it stands to reason it is logical or obviousit stands to reason that he will lose
  10. listen to reason to be persuaded peaceably
  11. reasons of State political justifications for an immoral act
verb
  1. (when tr, takes a clause as object) to think logically or draw (logical conclusions) from facts or premises
  2. (intr usually foll by with) to urge or seek to persuade by reasoning
  3. (tr often foll by out) to work out or resolve (a problem) by reasoning
Derived Formsreasoner, noun

Word Origin for reason

C13: from Old French reisun, from Latin ratiō reckoning, from rērī to think

usage

The expression the reason is because… should be avoided. Instead one should say either this is because… or the reason is that…
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 reason
n.

c.1200, "intellectual faculty that adopts actions to ends," also "statement in an argument, statement of explanation or justification," from Anglo-French resoun, Old French raison "course; matter; subject; language, speech; thought, opinion," from Latin rationem (nominative ratio) "reckoning, understanding, motive, cause," from ratus, past participle of reri "to reckon, think," from PIE root *re(i)- "to reason, count" (cf. Old English rædan "to advise; see read (v.)).

Meaning "sanity; degree of intelligence that distinguishes men from brutes" is recorded from late 13c. Sense of "grounds for action, motive, cause of an event" is from c.1300. Middle English sense of "meaning, signification" (early 14c.) is in the phrase rhyme or reason. Phrase it stands to reason is from 1630s. Age of Reason "the Enlightenment" is first recorded 1794, as the title of Tom Paine's book.

v.

early 14c., resunmen, "to question (someone)," also "to challenge," from Old French raisoner "speak, discuss; argue; address; speak to," from Late Latin rationare "to discourse," from ratio (see reason (n.)). Intransitive sense of "to think in a logical manner" is from 1590s; transitive sense of "employ reasoning (with someone)" is from 1847. Related: Reasoned; reasoning.

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with reason

reason

see by reason of; in reason; it stands to reason; listen to reason; lose one's mind (reason); rhyme or reason; see reason; stand to reason; with reason.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.