MEANING: noun: A joke or prank.
verb intr.: To joke or play a trick.
verb tr.: To mock or trick.

ETYMOLOGY: From Old French japer (to yap; Modern French japper), of imitative origin. Earliest documented use: 1362.

JA, PEU - Overheard in a café in Strasbourg, after "Would you like a some more coffee?"

J.A. PEI - the architect's younger brother

JA, pp- response to "Even softer, Herr Beethoven?