under

To go suddenly under the surface of a body of water after a period of floating.

To make (someone or something) subject to (something else); to place (someone) in a state of (something).

To remain beneath a level.

To reluctantly accept something (due to a source of social pressure).

To purchase (something) that (somebody else) intends to buy.

To come underneath (something).

To undersell or undercut; to offer a product at a lower price than someone else.

In Australia.

To drink more alcohol than another person, possibly to the point of that person passing out.

To belong to for purposes of categorization.

To go unnoticed, especially for a long period of time.

To give up without or with little reason.

To escape from a debt.

To sharply steer the other direction (e.g. to switch from right to left) when backing up in order to align a truck straight on with a loading dock.

To irritate someone.

To descend into a body of water; to founder.

To conceal one's positive qualities or talents, especially due to modesty or shyness; to avoid attention.

Angry; agitated.

To hold in subjection; hence, to oppress.

To acknowledge oneself conquered; to submit, to yield.