What is a valley or low place; a tract of low, and usually wet, land; a moor; a fen. [Prov. Eng. & Local, U.S.] called?

swale — A valley or low place; a tract of low, and usually wet, land; a moor; a fen. [Prov. Eng. & Local, U.S.]. (Webster's 1913.)

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