Word Study
wapper
CIDE DICTIONARY
wapper, 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. [1913 Webster]
wapper, n.
A gudgeon. [1913 Webster]
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