side vs rear

side and rear both are nouns.

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

As nouns, rear is a hyponym of side; that is, rear is a word with a more specific, narrower meaning than side:

As nouns, rear is a hyponym of side; that is, rear is a word with a more specific, narrower meaning than side:

side (noun)	rear (noun)
an extended outer surface of an object	the side that goes last or is not normally seen
either the left or right half of a body	the fleshy part of the human body that you sit on
an aspect of something (as contrasted with some other implied aspect)	the back of a military formation or procession
an opinion that is held in opposition to another in an argument or dispute	the side of an object that is opposite its front
(sports) the spin given to a ball by striking it on one side or releasing it with a sharp twist	the part of something that is furthest from the normal viewer
a lengthwise dressed half of an animal's carcass used for food
one of two or more contesting groups
a family line of descent
a surface forming part of the outside of an object
a line segment forming part of the perimeter of a plane figure
a place within a region identified relative to a center or reference location
an elevated geological formation

side (adjective)	rear (adjective)
located on a side	located in or toward the back or rear

side (verb)	rear (verb)
take sides for or against	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