wapper

Wap"per, v. t. & i. Etym: [freq. of wap, v.; cf. dial. G. wappern, wippern, to move up and down, to rock.] Defn: To cause to shake; to tremble; to move tremulously, as from weakness; to totter. [Obs.] Wap"per, n. (Zoöl.) Defn: A gudgeon. [Prov. Eng.]

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