v. & n.
v. (past swore; past part. sworn) 1 tr. a (often foll. by to + infin. or that + clause) state or promise solemnly or on oath. b take (an oath). 2 tr. colloq. say emphatically; insist (swore he had not seen it). 3 tr. cause to take an oath (swore them to secrecy). 4 intr. (often foll. by at) use profane or indecent language, esp. as an expletive or from anger. 5 tr. (often foll. by against) make a sworn affirmation of (an offence) (swear treason against). 6 intr. (foll. by by) a appeal to as a witness in taking an oath (swear by Almighty God). b colloq. have or express great confidence in (swears by yoga). 7 intr. (foll. by to; usu. in neg.) admit the certainty of (could not swear to it). 8 intr. (foll. by at) colloq. (of colours etc.) fail to harmonize with.
n. a spell of swearing. swear blind colloq. affirm emphatically. swear in induct into office etc. by administering an oath. swear off colloq. promise to abstain from (drink etc.). swear-word a profane or indecent word, esp. uttered as an expletive. swearer n.
[ OE swerian f. Gmc, rel. to ANSWER ]