In biology, the crossing and selection of animals and plants to change the characteristics of an existing breed or cultivar (variety), or to produce a new one.
Cattle may be bred for increased meat or milk yield, sheep for thicker or finer wool, and horses for speed or stamina. Plants, such as wheat or corn, may be bred for disease resistance, heavier and more rapid cropping, and hardiness to adverse weather.
1. Raising someone to be an accepted member of the community; SYN. bringing up, fostering, fosterage, nurture, nurturing, raising, rearing, upbringing.
2. General education, usually associate with high culture.
3. The production of livestock for human consumption.
4. The production of animals or plants by inbreeding or hybridization.

Producing offspring or set aside especially for producing offspring.

In nuclear physics, a process in a reactor in which more fissionable material is produced than is consumed in running the reactor.
For example, plutonium-239 can be made from the relatively plentiful (but nonfissile) uranium-238, or uranium-233 can be produced from thorium. The Pu-239 or U-233 can then be used to fuel other reactors. The French breeder reactor Superphénix, one of the most successful, generates 250 megawatts of electrical power.