Source : Webster's Revised Unabridged Dictionary (1913)

Undifferentiated \Un*dif`fer*en"ti*a`ted\, a.
   Not differentiated; specifically (Biol.), homogenous, or
   nearly so; -- said especially of young or embryonic tissues
   which have not yet undergone differentiation (see
   {Differentiation}, 3), that is, which show no visible
   separation into their different structural parts.

Source : WordNet®

undifferentiated
     adj : not differentiated [syn: {uniform}] [ant: {differentiated}]