Wap"per (?), v. t. & i. [freq. of wap, v.; cf. dial. G. wappern, wippern, to move up and down, to rock.]
To cause to shake; to tremble; to move tremulously, as from weakness; to totter.
[Obs.]
© Webster 1913.
Wap"per (?), n. Zool.
A gudgeon.
[Prov. Eng.]
<-- ## The Zool. mark was in square brackets, inconsistent with normal usage. -->
© Webster 1913.