quaternate vs quaternary

quaternate is not a noun while quaternary is a noun.

Word	Noun	Adjective	Verb	Adverb
quaternate	No	Yes	No	No
quaternary	Yes	Yes	No	No

As adjectives, quaternate and quaternary are synonyms defined as:

quaternate and quaternary: consisting of or especially arranged in sets of four

quaternate (noun)	quaternary (noun)
	the cardinal number that is the sum of three and one

quaternate (adjective)	quaternary (adjective)
consisting of or especially arranged in sets of four	consisting of or especially arranged in sets of four
	coming next after the third and just before the fifth in position or time or degree or magnitude