Emily Dickinson Lexicon

RI'DER, n.

1. One who is borne on a horse or other beast, or in a vehicle.
2. One who breaks or manages a horse. – Shak.
3. The matrix of an ore. – Gregory.
4. An inserted leaf or an additional clause, as to a bill in parliament.
5. In ship building, a sort of interior rib fixed occasionally in a ship'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. – Mar. Dict.