rearward vs rear

rearward and rear both are nouns.

Word	Noun	Adjective	Verb	Adverb
rearward	Yes	Yes	No	Yes
rear	Yes	Yes	Yes	No

As adjectives, rearward and rear are synonyms defined as:

As nouns, rear is a hypernym of rearward; that is, rear is a word with a broader meaning than rearward:

Other hypernyms of rearward include back end, backside.

rearward (noun)	rear (noun)
direction toward the rear	the side that goes last or is not normally seen
	the fleshy part of the human body that you sit on
	the back of a military formation or procession
	the side of an object that is opposite its front
	the part of something that is furthest from the normal viewer

rearward (adjective)	rear (adjective)
located in or toward the back or rear	located in or toward the back or rear
directed or moving toward the rear

rearward (verb)	rear (verb)
	construct, build, or erect
	stand up on the hind legs, of quadrupeds
	cause to rise up
	look after a child until it is an adult
	rise up

rearward (adverb)	rear (adverb)
at or to or toward the back or rear