quaternary vs quaternate

quaternary is a noun but quaternate is not a noun.

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

As adjectives, quaternary and quaternate are synonyms defined as:

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

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

quaternary (adjective)	quaternate (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