Source : Webster's Revised Unabridged Dictionary (1913)

Inessential \In`es*sen"tial\, a. [Pref. in- not + essential: cf.
   F. inessentiel.]
   1. Having no essence or being. --H. Brooke.

            The womb of inessential Naught.       --Shelley.

   2. Not essential; unessential.

Source : WordNet®

inessential
     adj 1: not basic or fundamental [syn: {unessential}] [ant: {essential}]
     2: not absolutely necessary

inessential
     n : anything that is not essential; "they discarded all their
         inessentials" [syn: {nonessential}] [ant: {necessity}]