As nouns the difference between wapper and swapper
is that wapper is (uk|dialect) a gudgeon while swapper is agent noun of swap; one who swaps.
As a verb wapper
is to cause to shake; to move tremulously, as from weakness; to totter.
wapper
English
Etymology 1
Noun
(
en noun)
(UK, dialect) A gudgeon.
Etymology 2
Frequentative of wap; compare (etyl) dialect wappern, wippern, to move up and down, to rock.
Verb
(
en verb)
To cause to shake; to move tremulously, as from weakness; to totter.
(
Webster 1913)
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