Rangifer tarandus vs cervid

Rangifer tarandus and cervid both are nouns.

Word	Noun	Adjective	Verb	Adverb
Rangifer tarandus	Yes	No	No	No
cervid	Yes	No	No	No

As nouns, cervid is a hypernym of Rangifer tarandus; that is, cervid is a word with a broader meaning than Rangifer tarandus:

Rangifer tarandus: Arctic deer with large antlers in both sexes; called `reindeer' in Eurasia and `caribou' in North America
cervid: distinguished from Bovidae by the male's having solid deciduous antlers

Other hypernyms of Rangifer tarandus include deer.

Rangifer tarandus (noun)	cervid (noun)
Arctic deer with large antlers in both sexes; called `reindeer' in Eurasia and `caribou' in North America	distinguished from Bovidae by the male's having solid deciduous antlers