behindhand vs behind

behindhand is not a noun while behind is a noun.

Word	Noun	Adjective	Verb	Adverb
behindhand	No	Yes	No	Yes
behind	Yes	Yes	No	Yes

As adverbs, behindhand and behind are synonyms defined as:

Other synonyms of behindhand include in arrears.

behindhand (noun)	behind (noun)
	the fleshy part of the human body that you sit on

behindhand (adjective)	behind (adjective)
behind schedule	having the lower score or lagging position in a contest

behindhand (adverb)	behind (adverb)
in debt	in or to or toward the rear
	remaining in a place or condition that has been left or departed from
	in debt
	in or into an inferior position
	showing a time that is earlier than the actual time