SWEAR
—verb. (past swore; past part. Sworn) 1 a (often foll. By to + infin. Or that + clause) state or promise solemnly or on oath. B (cause to) take (an oath) (swore them to secrecy). 2 colloq. Insist (swore he was fit). 3 (often foll. By at) use profane or obscene language. 4 (foll. By by) a appeal to as a witness in taking an oath (swear by almighty god). B colloq. Have great confidence in (swears by yoga). 5 (foll. By to; usually. In neg.) Say certainly (could not swear to it). —none. Spell of swearing. ? swear blind colloq. Affirm emphatically. Swear in induct into office etc. With an oath. Swear off colloq. Promise to abstain from (drink etc.). [old english]