Frith (fr&ibreve_;th), n. [OE. firth, Icel. fjörðr; akin to Sw. fjärd, Dan. fiord, E. ford. √78. See Ford, n., and cf. Firth, Fiord, Fret a frith, Port a harbor.]
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1. (Geog.) A narrow arm of the sea; an estuary; the opening of a river into the sea; as, the Frith of Forth. Also called firth.
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2. A kind of weir for catching fish. [Eng.] Carew.
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