BREEDER

n. one who breeds or raises animals

A breeder is a person who practices the vocation of mating carefully selected specimens of the same breed to reproduce specific, consistently replicable qualities and characteristics.This might be as a farmer, agriculturalist, or hobbyist, and can be practiced on a large or small scale, for food, fun, or profit."Breeder" is also a derogatory term used by homosexuals when regarding non-homosexuals.
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Noun
1. a person who breeds animals
(synonym) stock breeder
(hypernym) stockman, stock raiser, stock farmer
(derivation) breed

(n.)
One who, or that which, breeds, produces, brings up, etc.
  

(n.)
A cause.
  

A reactor that produces more nuclear fuel than it consumes. A fertile material, such as uranium-238, when bombarded by neutrons, is transformed into a fissile material, such as plutonium-239, which can be used as fuel.