verb Cannot (negative modal auxiliary); be unable to; not have the ability to (whether due to lacking relevant strength or skill or knowledge or supplies, or due to logical impossibility, etc).
I can’t quite get it to work.
verb To be forbidden to; to be not permitted to.
You can’t enter the hall without a ticket.
verb To be unwilling to; to not have the desire of; to don’t want to.
Will you come to dinner with us tonight? Can't; already have plans this evening.