The Collaborative International Dictionary of English v.0.48:

Unlisted \Unlisted\
   See listed.

The Collaborative International Dictionary of English v.0.48:

Unlisted \Un*list"ed\, a.
   Not listed; specif.
   (a) (New York Stock Exchange), admitted to quotation in the
       unlisted department, that is, admitted to be dealt in on
       the floor, but not to the "regular list."
   (b) not listed in the telephone directory; -- of telephone
       numbers; as, an unlisted number.
       [Webster 1913 Suppl. +PJC]

WordNet (r) 3.0 (2006):

unlisted
    adj 1: not on a list; "an unlisted telephone number" [ant:
           listed]
    2: not having your name entered on a voting list; "an unlisted
       voter"