front end vs forefront

front end and forefront both are nouns.

Word	Noun	Adjective	Verb	Adverb
front end	Yes	No	No	No
forefront	Yes	No	No	No

As nouns, forefront is a hyponym of front end; that is, forefront is a word with a more specific, narrower meaning than front end:

Other hyponyms of front end include head.

front end (noun)	forefront (noun)
the side that is forward or prominent	the position of greatest importance or advancement; the leading position in any movement or field
	the part in the front or nearest the viewer