breed has 6 distinct synonyms spread across 4 of its 6 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
copulate with a female, used especially of horses
“The horse covers the mare”
Synonyms, antonyms and the broader and narrower relations for breed come from Princeton University’s WordNet. Full sources and licences.
cause to procreate (animals)
“She breeds dogs”
a special variety of domesticated animals within a species
“he experimented on a particular breed of white rats”
a special type
“Google represents a new breed of entrepreneurs”