Check: Small word, loads of different meanings. One of the most common is "to inspect or verify." You might check the oven to see if your cookies are done.
A few of the many meanings of check: As a noun: the act of restraining power or action; a pattern of squares resembling a checkerboard; a restaurant bill; a financial instrument payable to the named bearer (from your checkbook); a mark indicating that something's been noted or finished. As a verb: to crack on the surface; to slow or delay growth; to obstruct your hockey opponent; to hand over for inventory and safekeeping, especially baggage on a plane.