back vs cover

back and cover both are nouns.

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

As nouns, back and cover are synonyms defined as:

back and cover: the protective covering on the front, back, and spine of a book

Other synonyms of back include binding, book binding.

back (noun)	cover (noun)
(American football) the position of a player on a football team who is stationed behind the line of scrimmage	the act of concealing the existence of something by obstructing the view of it
the side that goes last or is not normally seen	fire that makes it difficult for the enemy to fire on your own individuals or formations
a support that you can lean against while sitting	a false identity and background (especially one created for an undercover agent)
the part of a garment that covers the back of your body	a recording of a song that was first recorded or made popular by somebody else
the protective covering on the front, back, and spine of a book	bedding that keeps a person warm in bed
the posterior part of a human (or animal) body from the neck to the end of the spine	a covering that serves to conceal or shelter something
the series of vertebrae forming the axis of the skeleton and protecting the spinal cord	covering for a hole (especially a hole in the top of a container)
the part of something that is furthest from the normal viewer	the protective covering on the front, back, and spine of a book
(football) a person who plays in the backfield	a natural object that covers or envelops
	a fixed charge by a restaurant or nightclub over and above the charge for food and drink

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

back (verb)	cover (verb)
establish as valid or genuine	sit on (eggs)
strengthen by providing with a back or backing	clothe, as if for protection from the elements
shift to a counterclockwise direction	protect by insurance
place a bet on	act on verbally or in some form of artistic expression
travel backward	be responsible for reporting the details of, as in journalism
cause to travel backward	maintain a check on; especially by patrolling
support financial backing for	protect or defend (a position in a game)
be behind; approve of	hold within range of an aimed firearm
give support or one's approval to	play a higher card than the one previously played
be in back of	be responsible for guarding an opponent in a game
	provide with a covering or cause to be covered
	form a cover over
	copulate with a female, used especially of horses
	cover as if with a shroud
	put something on top of something else
	travel across or pass over
	hide from view or knowledge
	spread over a surface to conceal or protect
	be sufficient to meet, defray, or offset the charge or cost of
	to take an action to protect against future problems
	invest with a large or excessive amount of something
	help out by taking someone's place and temporarily assuming his responsibilities
	provide for
	span an interval of distance, space or time
	include in scope; include as part of something broader; have as one's sphere or territory
	make up for shortcomings or a feeling of inferiority by exaggerating good qualities

back (adverb)	cover (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
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