cover vs sheet

cover and sheet both are nouns.

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

As verbs, sheet is a hyponym of cover; that is, sheet is a word with a more specific, narrower meaning than cover:

cover (noun)	sheet (noun)
the act of concealing the existence of something by obstructing the view of it	bed linen consisting of a large rectangular piece of cotton or linen cloth; used in pairs
fire that makes it difficult for the enemy to fire on your own individuals or formations	(nautical) a line (rope or chain) that regulates the angle at which a sail is set in relation to the wind
a false identity and background (especially one created for an undercover agent)	a flat artifact that is thin relative to its length and width
a recording of a song that was first recorded or made popular by somebody else	a large piece of fabric (usually canvas fabric) by means of which wind is used to propel a sailing vessel
bedding that keeps a person warm in bed	paper used for writing or printing
a covering that serves to conceal or shelter something	newspaper with half-size pages
covering for a hole (especially a hole in the top of a container)	any broad thin expanse or surface
the protective covering on the front, back, and spine of a book	(mathematics) an unbounded two-dimensional shape
a natural object that covers or envelops
a fixed charge by a restaurant or nightclub over and above the charge for food and drink

cover (verb)	sheet (verb)
sit on (eggs)	cover with a sheet, as if by wrapping
clothe, as if for protection from the elements	come down as if in sheets
protect by insurance
act on verbally or in some form of artistic expression
be responsible for reporting the details of, as in journalism
maintain a check on; especially by patrolling
protect or defend (a position in a game)
hold within range of an aimed firearm
play a higher card than the one previously played
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