RIDER

n. person or thing which who rides; addition or appendix to a document

A rider can refer to:An equestrian (horse rider)A cyclistA passenger (usually) of a vehicle (i.e. motorcyclist)Dispatch rider, a soldier generally riding a motorcycle whose duty is to safely collect and deposit reports and information files from one location to another Rider (legislation), an additional provision attached to a bill under the consideration of a legislative assemblyRider (insurance), an amendment to an insurance contract expanding the coverage provided by the contract and (in most cases) increasing the premiumRider (theater), a part of a performers contractRider University, a United States institution for higher education
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Noun
1. a traveler who actively rides an animal (as a horse or camel)
(hypernym) traveler, traveller
(hyponym) hang glider
(derivation) ride, sit
2. a clause that is appended to a legislative bill
(hypernym) article, clause
(part-holonym) bill, measure
3. a traveler who actively rides a vehicle (as a bicycle or motorcycle)
(hypernym) traveler, traveller
(derivation) ride
4. a traveler riding in a vehicle (a boat or bus or car or plane or train etc) who is not operating it
(synonym) passenger
(hypernym) traveler, traveller
(hyponym) commuter
(derivation) ride
(classification) boat

v. wrinkle, ruffle; corrugate, furrow, line

(n.)
The second tier of casks in a vessel's hold.
  

(n.)
Rock material in a vein of ore, dividing it.
  

(n.)
One who, or that which, rides.
  

(n.)
One who breaks or manages a horse.
  

(n.)
Formerly, an agent who went out with samples of goods to obtain orders; a commercial traveler.
  

(n.)
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.
  

(n.)
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.
  

(n.)
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.
  

(n.)
A robber.
  

(n.)
A problem of more than usual difficulty added to another on an examination paper.
  

(n.)
A Dutch gold coin having the figure of a man on horseback stamped upon it.