truncate vs truncation

truncate is not a noun while truncation is a noun.

Word	Noun	Adjective	Verb	Adverb
truncate	No	Yes	Yes	No
truncation	Yes	No	No	No

truncate (noun)	truncation (noun)
	the act of cutting short
	the replacement of an edge or solid angle (as in cutting a gemstone) by a plane (especially by a plane that is equally inclined to the adjacent faces)
	the property of being truncated or short

truncate (adjective)	truncation (adjective)
terminating abruptly by having or as if having an end or point cut off

truncate (verb)	truncation (verb)
make shorter as if by cutting off
approximate by ignoring all terms beyond a chosen one
replace a corner by a plane