breed (n.) Look up breed at Dictionary.com
"race, lineage, stock" (originally of animals), 1550s, from breed (v.). Of persons, from 1590s. Meaning "kind, species" is from 1580s.
breed (v.) Look up breed at Dictionary.com
Old English bredan "bring young to birth, carry," also "cherish, keep warm," from West Germanic *brodjan (source also of Old High German bruoten, German brüten "to brood, hatch"), from *brod- "fetus, hatchling," from PIE root *bhreu- "to boil, bubble, effervesce, burn." Original notion of the word was incubation, warming to hatch. Sense of "grow up, be reared" (in a clan, etc.) is late 14c. Related: Bred; breeding.