rider

Short definition from Wiktionary

Noun

1. 1
   A mounted person: A knight, or other mounted warrior.
2. 2
   A mounted person: An old Dutch gold coin with the figure of a man on horseback stamped upon it.
3. 3
   A mounted person: Someone who rides a horse or (later) a bicycle, motorcycle etc.
4. 4
   A mounted person: A mounted robber; a bandit, especially in the Scottish borders.
5. 5
   A mounted person: Someone who breaks in or manages a horse; a riding master.
6. 6
   A mounted person: An agent who goes out with samples of goods to obtain orders; a commercial traveller or travelling salesman.
7. 7
   A mounted person: Someone riding in a vehicle; a passenger on public transport.
8. 8
   A boarder, a person who rides a board in boardsports: A skateboarder
9. 9
   A boarder, a person who rides a board in boardsports: A snowboarder
10. 10
    An addition, supplement: A supplementary clause added to a document after drafting, especially to a bill under the consideration of a legislature.
11. 11
    An addition, supplement: An amendment or addition to an entertainer's performance contract, often covering a performer's equipment or food, drinks, and general comfort requirements.
12. 12
    An addition, supplement: An additional matter or question arising in corollary; a qualification.
13. 13
    An addition, supplement: A supplementary question, now especially in mathematics.
14. 14
    An addition, supplement: An add-on to an insurance policy.
15. 15
    Technical senses: An interior rib occasionally fixed in a ship's hold, reaching from the keelson to the beams of the lower deck, to strengthen the frame.
16. 16
    Technical senses: Rock material in a vein of ore, dividing it.
17. 17
    Technical senses: The second tier of casks in a vessel's hold.
18. 18
    Technical senses: A small, sliding piece of thin metal on a balance, used to determine small weights.
19. 19
    Technical senses: The first Lenormand card, also known as either the horseman or the cavalier.
20. 20
    Technical senses: A piece, such as the rook or bishop, which moves any distance in one direction as long as no other piece is in the way.

Proper noun

1. 1
   A surname originating as an occupation. More often spelled Ryder.