horseleech vs bloodsucker

horseleech and bloodsucker both are nouns.

Word	Noun	Adjective	Verb	Adverb
horseleech	Yes	No	No	No
bloodsucker	Yes	No	No	No

As nouns, bloodsucker is a hypernym of horseleech; that is, bloodsucker is a word with a broader meaning than horseleech:

horseleech: any of several large freshwater leeches
bloodsucker: carnivorous or bloodsucking aquatic or terrestrial worms typically having a sucker at each end

Other hypernyms of horseleech include hirudinean, leech.

horseleech (noun)	bloodsucker (noun)
any of several large freshwater leeches	carnivorous or bloodsucking aquatic or terrestrial worms typically having a sucker at each end