reindeer vs Greenland caribou

reindeer and Greenland caribou both are nouns.

Word	Noun	Adjective	Verb	Adverb
reindeer	Yes	No	No	No
Greenland caribou	Yes	No	No	No

As nouns, reindeer and Greenland caribou are synonyms defined as:

reindeer and Greenland caribou: Arctic deer with large antlers in both sexes; called `reindeer' in Eurasia and `caribou' in North America

Other synonyms of reindeer include caribou, Rangifer tarandus.

reindeer (noun)	Greenland caribou (noun)
Arctic deer with large antlers in both sexes; called `reindeer' in Eurasia and `caribou' in North America	Arctic deer with large antlers in both sexes; called `reindeer' in Eurasia and `caribou' in North America