1.One who, or that which, rides.
2.Formerly, an agent who went out with samples of goods to obtain orders; a commercial traveler. (Eng.)
3.One who breaks or manages a horse.
4.An addition or amendment to a manuscript or other document, which is attached on a separate piece of paper; in legislative practice, an additional clause annexed to a bill while in course of passage; something extra or burdensome that is imposed. "After the third reading, a foolish man stood up to propose a rider." "This (question) was a rider which Mab found difficult to answer."
5.(Math.) A problem of more than usual difficulty added to another on an examination paper.
6.A Dutch gold coin having the figure of a man on horseback stamped upon it. "His moldy money! half a dozen riders."
7.(Mining) Rock material in a vein of ore, dividing it.
8.(Shipbuilding) An interior rib occasionally fixed in a ship's hold, reaching from the keelson to the beams of the lower deck, to strengthen her frame.
9.(Naut.) The second tier of casks in a vessel's hold.
10.A small forked weight which straddles the beam of a balance, along which it can be moved in the manner of the weight on a steelyard.
11.A robber. (Obs. or Prov. Eng.)
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