[kon-shuh ns]


the inner sense of what is right or wrong in one's conduct or motives, impelling one toward right action: to follow the dictates of conscience.
the complex of ethical and moral principles that controls or inhibits the actions or thoughts of an individual.
an inhibiting sense of what is prudent: I'd eat another piece of pie but my conscience would bother me.
Obsolete. consciousness; self-knowledge.
Obsolete. strict and reverential observance.


    have something on one's conscience, to feel guilty about something, as an act that one considers wrong: She behaves as if she had something on her conscience.
    in all conscience,
    1. in all reason and fairness.
    2. certainly; assuredly.
    Also in conscience.

Origin of conscience

1175–1225; Middle English < Anglo-French < Latin conscientia knowledge, awareness, conscience. See con-, science
Related formscon·science·less, adjectivecon·science·less·ly, adverbcon·science·less·ness, nounsub·con·science, noun
Can be confusedconscience conscious Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for conscienceless

immoral, ruthless, unconscionable, unethical, unprincipled, amoral

Examples from the Web for conscienceless

Contemporary Examples of conscienceless

Historical Examples of conscienceless

  • He had none of the direct, passionate, conscienceless resolution of Laertes.

  • The wound she had received from Philip had left her conscienceless towards Pete.

    The Manxman

    Hall Caine

  • The village life abounds with jokers, Shiftless, conscienceless and shrewd.

    Prairie Folks

    Hamlin Garland

  • I will help him throw off the shackles with which conscienceless capitalism has fettered him.

    The Mask

    Arthur Hornblow

  • If you want to and if I want you to, it shows that you are cruel and I conscienceless.

    The Dull Miss Archinard

    Anne Douglas Sedgwick

British Dictionary definitions for conscienceless



  1. the sense of right and wrong that governs a person's thoughts and actions
  2. regulation of one's actions in conformity to this sense
  3. a supposed universal faculty of moral insight
conscientiousness; diligence
a feeling of guilt or anxietyhe has a conscience about his unkind action
obsolete consciousness
in conscience or in all conscience
  1. with regard to truth and justice
  2. certainly
on one's conscience causing feelings of guilt or remorse
Derived Formsconscienceless, adjective

Word Origin for conscience

C13: from Old French, from Latin conscientia knowledge, consciousness, from conscīre to know; see conscious
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 conscienceless



early 13c., from Old French conscience "conscience, innermost thoughts, desires, intentions; feelings" (12c.), from Latin conscientia "knowledge within oneself, sense of right, a moral sense," from conscientem (nominative consciens), present participle of conscire "be (mutually) aware," from com- "with," or "thoroughly" (see com-) + scire "to know" (see science).

Probably a loan-translation of Greek syneidesis, literally "with-knowledge." Sometimes nativized in Old English/Middle English as inwit. Russian also uses a loan-translation, so-vest, "conscience," literally "with-knowledge."

Online Etymology Dictionary, © 2010 Douglas Harper

conscienceless in Medicine




The awareness of a moral or ethical aspect to one's conduct together with the urge to prefer right over wrong.
The part of the superego that judges the ethical nature of one's actions and thoughts and then transmits such determinations to the ego for consideration.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Idioms and Phrases with conscienceless


see have a clear conscience; in conscience.

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