Whap (?), Whop, v. i. [Cf. OE. quappen to palpitate, E. quob, quaver, wabble, awhape, wap.]
To throw one's self quickly, or by an abrupt motion; to turn suddenly; as, she whapped down on the floor; the fish whapped over.
Bartlett.
⇒ This word is used adverbially in the north of England, as in the United States, when anything vanishes, or is gone suddenly; as, whap went the cigar out of my mouth.
© Webster 1913.
Whap, Whop, v. t. [imp. & p. p. Whapped (?); p. pr. & vb. n. Whapping.]
To beat or strike.
© Webster 1913.
Whap, Whop, n.
A blow, or quick, smart stroke.
© Webster 1913.