[f. FLOW v. + -AGE.] The act of flowing; the state of being flowed or flooded. In comb. flowage-line.

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1846.  Worcester cites Wilkins.

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1884.  J. G. Pyle, The Reservoir System, in Harper’s Mag., LXIX. Sept., 621/1, diagram. Flowage line [of a reservoir].

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