verb (used with object), for·swore, for·sworn, for·swearing.

to reject or renounce under oath: to forswear an injurious habit.
to deny vehemently or under oath.
to perjure (oneself).

verb (used without object), for·swore, for·sworn, for·swearing.

to swear falsely; commit perjury.

Origin of forswear

before 900; Middle English forsweren, Old English forswerian. See for-, swear
Related formsfor·swear·er, noun

Synonyms for forswear Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for forswear

Contemporary Examples of forswear

Historical Examples of forswear

  • The old girl must be protected from that sort of eye-opener, if I've to forswear my soul.


    Joseph Conrad and F.M. Hueffer

  • He would not forswear his fathers' faith and did not understand what the priest said.

    From Pole to Pole

    Sven Anders Hedin

  • “Then I forswear all rash promises for the future,” he declared.

    That Girl Montana

    Marah Ellis Ryan

  • All the world seemed bent on compelling her to forswear herself.

    The Madigans

    Miriam Michelson

  • What is the secret of thy ring that a man must forswear love for it?

    Operas Every Child Should Know

    Mary Schell Hoke Bacon

British Dictionary definitions for forswear


verb -swears, -swearing, -swore or -sworn

(tr) to reject or renounce with determination or as upon oath
(tr) to deny or disavow absolutely or upon oathhe forswore any knowledge of the crime
to perjure (oneself)
Derived Formsforswearer, noun

Word Origin for forswear

Old English forswearian
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 forswear

Old English forswerian "swear falsely," also "abandon or renounce on oath," from for- "completely" + swerian "to swear." Related: Forswore; forsworn; forswearing.

Online Etymology Dictionary, © 2010 Douglas Harper