Wordnet 3.0
NOUN (1)
1. 
 an alien who paid a fee to reside in an ancient Greek city; 
The Collaborative International Dictionary of English v.0.48:
Metic \Met"ic\ (? or ?; 277), n. [Gr. ?, prop., changing one's
   abode; ?, indicating change + ? house, abode: cf. L.
   metoecus, F. m['e]t[`e]que.] (Gr. Antiq.)
   A sojourner; an immigrant; an alien resident in a Grecian
   city, but not a citizen. --Mitford.
   [1913 Webster]
         The whole force of Athens, metics as well as citizens,
         and all the strangers who were then in the city.
                                                  --Jowett
                                                  (Thucyd. ).
   [1913 Webster]
WordNet (r) 3.0 (2006):
metic
    n 1: an alien who paid a fee to reside in an ancient Greek city