Swear1, v. i.
(4), v. i. [imp. SWORE (formerly SWARE); p. p. SWORN; p. pr. & vb. n. SWEARING.] [A-S. & O. H. Ger. swerian, O. Sax. suerian, Goth. svaran, L. Ger. swören, D. zweren, N. H. Ger. schwören, O. Fries. svera, Icel. sveria, Sw. svärja, Dan. svärge, allied to A-S. swarian, to affirm, to answer, Icel. & Sw. svara, Dan. svare, to answer, q. v.]
Sense 1. To affirm or utter a solemn declaration, with an appeal to God for the truth of what is affirmed.
I swear by all the Roman gods. Shak.
Sense 2. (Law.) To give evidence on oath; as, to swear to the truth of a statement; he swore that the prisoner was not present at the riot.
Sense 3. To make an appeal to God in an irreverent manner; to use the name of God or sacred things profanely.