separate vs secernate

separate is a noun but secernate is not a noun.

Word	Noun	Adjective	Verb	Adverb
separate	Yes	Yes	Yes	No
secernate	No	No	Yes	No

As verbs, separate and secernate are synonyms defined as:

Other synonyms of separate include differentiate, distinguish, secern, severalise, severalize, tell, tell apart.

As verbs, secernate is a hypernym of separate; that is, secernate is a word with a broader meaning than separate:

Other hypernyms of separate include differentiate, distinguish, secern, separate, severalise, severalize, tell, tell apart.

separate (noun)	secernate (noun)
a garment that can be purchased separately and worn in combinations with other garments
a separately printed article that originally appeared in a larger publication

separate (adjective)	secernate (adjective)
independent; not united or joint
standing apart; not attached to or supported by anything
separated according to race, sex, class, or religion
have the connection undone; having become separate

separate (verb)	secernate (verb)
become separated into pieces or fragments	mark as different
divide into two or more branches so as to form a fork
arrange or order by classes or categories
mark as different
move or break apart
force, take, or pull apart
divide into components or constituents
go one's own way; move apart
make a division or separation
treat differently on the basis of sex or race
separate into parts or portions
discontinue an association or relation; go different ways
act as a barrier between; stand between