back vs position

back and position both are nouns.

Word	Noun	Adjective	Verb	Adverb
back	Yes	Yes	Yes	Yes
position	Yes	No	Yes	No

As nouns, position is a hypernym of back; that is, position is a word with a broader meaning than back:

back: (American football) the position of a player on a football team who is stationed behind the line of scrimmage
position: (in team sports) the role assigned to an individual player

As nouns, position is a hypernym of back; that is, position is a word with a broader meaning than back:

Other hypernyms of back include place.

back (noun)	position (noun)
(American football) the position of a player on a football team who is stationed behind the line of scrimmage	the act of putting something in a certain place
the side that goes last or is not normally seen	a job in an organization
a support that you can lean against while sitting	(in team sports) the role assigned to an individual player
the part of a garment that covers the back of your body	the post or function properly or customarily occupied or served by another
the protective covering on the front, back, and spine of a book	the act of positing; an assumption taken as a postulate or axiom
the posterior part of a human (or animal) body from the neck to the end of the spine	the spatial property of a place where or way in which something is situated
the series of vertebrae forming the axis of the skeleton and protecting the spinal cord	the arrangement of the body and its limbs
the part of something that is furthest from the normal viewer	a way of regarding situations or topics etc.
(football) a person who plays in the backfield	a rationalized mental attitude
	an opinion that is held in opposition to another in an argument or dispute
	an item on a list or in a sequence
	the particular portion of space occupied by something
	a point occupied by troops for tactical reasons
	the appropriate or customary location
	the relative position or standing of things or especially persons in a society
	a condition or position in which you find yourself

back (adjective)	position (adjective)
related to or located at the back
of an earlier date
located at or near the back of an animal

back (verb)	position (verb)
establish as valid or genuine	put into a certain place or abstract location
strengthen by providing with a back or backing	cause to be in an appropriate place, state, or relation
shift to a counterclockwise direction
place a bet on
travel backward
cause to travel backward
support financial backing for
be behind; approve of
give support or one's approval to
be in back of

back (adverb)	position (adverb)
at or to or toward the back or rear
in or to or toward a past time
in repayment or retaliation
in or to or toward a former location
in or to or toward an original condition
in reply