Dam \Dam\, n. [Akin to OLG., D., & Dan. dam, G. & Sw. damm, Icel. dammr, and AS. fordemman to stop up, Goth. Fa['u]rdammjan.]

1. A barrier to prevent the flow of a liquid; esp., a bank of earth, or wall of any kind, as of masonry or wood, built across a water course, to confine and keep back flowing water.

2. (Metal.) A firebrick wall, or a stone, which forms the front of the hearth of a blast furnace.

Dam plate (Blast Furnace), an iron plate in front of the dam, to strengthen it.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Dam \Dam\, n. [OE. dame mistress, lady; also, mother, dam. See Dame.]

1. A female parent; -- used of beasts, especially of quadrupeds; sometimes applied in contempt to a human mother.

Our sire and dam, now confined to horses, are a relic of this age (13th century) . . . .Dame is used of a hen; we now make a great difference between dame and dam. --T. L. K. Oliphant.

The dam runs lowing up end down, Looking the way her harmless young one went. --Shak.

2. A kind or crowned piece in the game of draughts.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Dam \Dam\, v. t. [imp. & p. p. Dammed; p. pr. & vb. n. Damming.]

1. To obstruct or restrain the flow of, by a dam; to confine by constructing a dam, as a stream of water; -- generally used with in or up.

I'll have the current in this place dammed up. --Shak.

A weight of earth that dams in the water. --Mortimer.

2. To shut up; to stop up; to close; to restrain.

The strait pass was dammed With dead men hurt behind, and cowards. --Shak.

To dam out, to keep out by means of a dam.

Source: Webster's Revised Unabridged Dictionary (1913)