bull terrier vs terrier

bull terrier and terrier both are nouns.

Word	Noun	Adjective	Verb	Adverb
bull terrier	Yes	No	No	No
terrier	Yes	No	No	No

As nouns, terrier is a hypernym of bull terrier; that is, terrier is a word with a broader meaning than bull terrier:

bull terrier: a powerful short-haired terrier originated in England by crossing the bulldog with terriers
terrier: any of several usually small short-bodied breeds originally trained to hunt animals living underground

bull terrier (noun)	terrier (noun)
a powerful short-haired terrier originated in England by crossing the bulldog with terriers	any of several usually small short-bodied breeds originally trained to hunt animals living underground