breed vs interbreed

breed is a noun but interbreed is not a noun.

Word	Noun	Adjective	Verb	Adverb
breed	Yes	No	Yes	No
interbreed	No	No	Yes	No

As verbs, interbreed is a hyponym of breed; that is, interbreed is a word with a more specific, narrower meaning than breed:

breed: cause to procreate (animals)
interbreed: breed animals or plants using parents of different races and varieties

Other hyponyms of breed include mongrelise, mongrelize, cross, crossbreed, hybridise, hybridize.

breed (noun)	interbreed (noun)
a special type
a special variety of domesticated animals within a species

breed (verb)	interbreed (verb)
have young (animals) or reproduce (organisms)	breed animals or plants using parents of different races and varieties
copulate with a female, used especially of horses
cause to procreate (animals)
call forth