transitive. To prevent the passage of by blocking the channel or outlet. To dam, keep back, block the channel of (water, a stream, and the like)…

transitive or absol. To dam, obstruct the course of water, etc.

transitive. To stop, check; to dam up (a stream, or the like).

transitive. To dam up.

transitive. To furnish with a dam; to obstruct or confine (a stream, or water) by means of a dam. Usually with up; also (rarely) with back, out, etc.

transitive. To obstruct, dam (water): often with up, back.

transitive. To stop the flow of (water, etc.). Now only poetic (rare). Also, †to dam up.