The Collaborative International Dictionary of English v.0.48:

Occupant \Oc"cu*pant\, n. [L. occupans, p. pr. of occupare: cf.
   F. occupant. See Occupy.]
   1. One who occupies, or takes possession; one who has the
      actual use or possession, or is in possession, of a thing;
      as, the occupant of the apartment is not at home.
      [1913 Webster]

   Note: This word, in law, sometimes signifies one who takes
         the first possession of a thing that has no owner.
         [1913 Webster]

   2. A prostitute. [Obs.] --Marston.
      [1913 Webster]

WordNet (r) 3.0 (2006):

occupant
    n 1: someone who lives at a particular place for a prolonged
         period or who was born there [syn: resident, occupant,
         occupier] [ant: nonresident]