smoothen vs file

smoothen is not a noun while file is a noun.

Word	Noun	Adjective	Verb	Adverb
smoothen	No	No	Yes	No
file	Yes	No	Yes	No

As verbs, file is a hyponym of smoothen; that is, file is a word with a more specific, narrower meaning than smoothen:

Other hyponyms of smoothen include strip, launch, rake, plane, float, sand, sandpaper, sandblast.

smoothen (noun)	file (noun)
	a steel hand tool with small sharp teeth on some or all of its surfaces; used for smoothing wood or metal
	office furniture consisting of a container for keeping papers in order
	a set of related records (either written or electronic) kept together
	a line of persons or things ranged one behind the other

smoothen (verb)	file (verb)
become smooth	place in a container for keeping records
make smooth or smoother, as if by rubbing	file a formal charge against
make (a surface) shine	record in a public office or in a court of law
	smooth with a file
	proceed in line