What does forswear mean?
To forswear is to renounce something under oath — to swear solemnly that one will abandon a claim, habit, allegiance, or course of action. The word belongs to the family of formal, legal-sounding verbs and carries a weight of ceremony and finality: a knight might forswear violence, an exile might forswear their homeland, an addict might forswear drink. A second, older sense makes the word mean the opposite — to forswear oneself is to commit perjury, to swear falsely. This double meaning arises from the prefix 'for-', which in Old English construction could signal either negation or wrongdoing. Today the renunciation sense dominates, though the word remains formal and literary rather than conversational. Its irregular forms — forswear, forswore, forsworn — mirror those of swear itself. Found throughout Shakespeare and English legal history, forswear endures as the vocabulary of solemn, binding abjuration.
verbTo forswear something is to swear formally or solemnly to abandon, renounce, or give it up; it can also mean to commit perjury by falsely swearing.
- To renounce or give up something upon oath; to swear formally to abandon a habit, claim, or course of action.
- To deny something on oath, especially to commit perjury by swearing falsely.
"After the scandal, he forswore all future involvement in politics."
"The defeated general was forced to forswear all claims to the throne."
"She forswore smoking after her father's illness, swearing never to touch another cigarette."
Shakespeare used 'forswear' so often — across a dozen plays — that calling it an archaic relic would be, well, forswearing the truth.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of forswear
Forswear derives from the Old English verb 'forswerian', formed by attaching the prefix 'for-' to 'swerian' (to swear). The prefix served two functions: it could intensify toward renunciation, and it could mark the act negatively, giving rise to the perjury sense ('to forswear oneself'). The word is thus an indigenous Germanic formation rather than a Latin borrowing, with cognates in other Germanic languages such as Old Norse 'fyrirsverja'. It has been in continuous use since the medieval period and features prominently in Shakespeare's plays.
Related word forms
How forswear is actually used
Forswear is formal and somewhat literary in register, appearing more often in legal, historical, or dramatic contexts than in everyday conversation. Its inflected forms are irregular: 'forswear' becomes 'forswore' (past tense) and 'forsworn' (past participle), following the old pattern of 'swear/swore/sworn'. The second sense (perjury) is now rare and largely confined to historical or legal texts.
Easily confused with forswear
While 'swear' means to make a solemn vow or oath (or use profanity), 'forswear' means either to renounce something under oath or to perjure oneself — the 'for-' prefix signals giving up or falseness.