The Collaborative International Dictionary of English v.0.48:

Mao Tsetung \Mao Tsetung\, Mao Zedong \Mao Zedong\prop. n.
   The leader of the Chinese communist party and later of teh
   People's Repbulic of China; b. 1893, d. 1976. Also referred
   to a simply Mao. [Also spelled Mao Tse-Tung.]
   [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

Mao \Mao\ prop. n.
   See Mao Tsetung.
   [PJC]

WordNet (r) 3.0 (2006):

MAO
    n 1: an enzyme that catalyzes the oxidation of many body
         compounds (e.g., epinephrine and norepinephrine and
         serotonin) [syn: monoamine oxidase, MAO]
    2: Chinese communist leader (1893-1976) [syn: Mao, Mao
       Zedong, Mao Tsetung]

The Free On-line Dictionary of Computing (30 December 2018):

MAO

   An early symbolic mathematics system.

   [A. Rom, Celest Mech 1:309-319 (1969)].

   (1995-02-10)