cover has 50 distinct synonyms spread across 23 of its 36 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. Its one recorded opposite is uncover.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
provide for
“The grant doesn't cover my salary”
include in scope; include as part of something broader; have as one's sphere or territory
“This group encompasses a wide range of people from different backgrounds”
hold within range of an aimed firearm
to take an action to protect against future problems
“Count the cash in the drawer twice just to cover yourself”
protect or defend (a position in a game)
“he covered left field”
maintain a check on; especially by patrolling
“The second officer covered the top floor”
make up for shortcomings or a feeling of inferiority by exaggerating good qualities
“he is compensating for being a bad father”
invest with a large or excessive amount of something
“She covered herself with glory”
help out by taking someone's place and temporarily assuming his responsibilities
“She is covering for our secretary who is ill this week”
be sufficient to meet, defray, or offset the charge or cost of
“Is this enough to cover the check?”
spread over a surface to conceal or protect
“This paint covers well”
play a higher card than the one previously played
“Smith covered again”
be responsible for guarding an opponent in a game
a covering that serves to conceal or shelter something
“a screen of trees afforded privacy”
Synonyms, antonyms and the broader and narrower relations for cover come from Princeton University’s WordNet. Full sources and licences.
bedding that keeps a person warm in bed
“he pulled the covers over his head and went to sleep”
the act of concealing the existence of something by obstructing the view of it
“the cover concealed their guns from enemy aircraft”
the protective covering on the front, back, and spine of a book
“the book had a leather binding”
a natural object that covers or envelops
“under a covering of dust”
fire that makes it difficult for the enemy to fire on your own individuals or formations
“artillery provided covering fire for the withdrawal”
a fixed charge by a restaurant or nightclub over and above the charge for food and drink
a recording of a song that was first recorded or made popular by somebody else
“they made a cover of a Beatles' song”
a false identity and background (especially one created for an undercover agent)
“her new name and passport are cover for her next assignment”