separate vs rail off

separate is a noun but rail off is not a noun.

Word	Noun	Adjective	Verb	Adverb
separate	Yes	Yes	Yes	No
rail off	No	No	Yes	No

As verbs, rail off is a hyponym of separate; that is, rail off is a word with a more specific, narrower meaning than separate:

Other hyponyms of separate include partition, zone, break, break up, dispel, disperse, dissipate, scatter, rail, detach, close off, shut off.

separate (noun)	rail off (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)	rail off (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)	rail off (verb)
become separated into pieces or fragments	separate with a railing
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