cut across vs crosscut

cut across is not a noun while crosscut is a noun.

Word	Noun	Adjective	Verb	Adverb
cut across	No	No	Yes	No
crosscut	Yes	No	Yes	No

As verbs, cut across and crosscut are synonyms defined as:

cut across (noun)	crosscut (noun)
	a route shorter than the usual one
	a diagonal path

cut across (verb)	crosscut (verb)
cut using a diagonal line	cut using a diagonal line
travel across or pass over
be contrary to ordinary procedure or limitations