RI'DER, noun 1. One who is borne on a horse or other beast, or in a vehicle. 2. One who breaks or manages a horse. 3. The matrix of an ore. 4. An inserted leaf or an additional clause, as to a bill in parliament. 5. In ship building, a short of interior rib fixed occasionally in a ships's hold, opposite to some of the timbers to which they are bolted, and reaching from the keelson to the beams of the lower deck, to strengthen her frame.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI