separation vs threshing

separation and threshing both are nouns.

Word	Noun	Adjective	Verb	Adverb
separation	Yes	No	No	No
threshing	Yes	No	No	No

As nouns, threshing is a hyponym of separation; that is, threshing is a word with a more specific, narrower meaning than separation:

Other hyponyms of separation include sifting, winnow, winnowing.

separation (noun)	threshing (noun)
the social act of separating or parting company	the separation of grain or seeds from the husks and straw
the act of dividing or disconnecting
(law) the cessation of cohabitation of man and wife (either by mutual agreement or under a court order)
sorting one thing from others
the distance between things
coming apart
the termination of employment (by resignation or dismissal)
the space where a division or parting occurs
the state of lacking unity