Heenan's Universal Dictionary

A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - XYZ

XXXX
Confectioners' sugar label  [Anon]

XYZZY
Magic Word, password or cheat in many computer games.   [Anon]

YEAR
A period of three hundred and sixty-five disappointments.   [Ambrose Bierce]

YODA
Young Opinionated Directionless Artist.   [Palo Alto]

ZEAL
A nervous disorder afflicting the young and inexperienced.   [Ambrose Bierce]

ZENMAIL
Email with no text in the message body.   [Palo Alto]

ZEPPO
A waste of space; Excess baggage; The Fifth Marx Brother. [Buffy]