Source : Webster's Revised Unabridged Dictionary (1913)

Inoffensive \In"of*fen"sive\, a. [Pref. in- not + offensiue: cf.
   F. inoffensif.]
   1. Giving no offense, or provocation; causing no uneasiness,
      annoyance, or disturbance; as, an inoffensive man, answer,
      appearance.

   2. Harmless; doing no injury or mischief. --Dryden.

   3. Not obstructing; presenting no interruption bindrance.
      [R.] --Milton.

            So have Iseen a river gintly glide In a smooth
            course, and inoffensive tide.         --Addison.
      -- {In"of*fen"sive*ly}, adv. -- {In"of*fen"sive*ness}, n.

Source : WordNet®

inoffensive
     adj 1: not causing anger or annoyance; "inoffensive behavior" [syn:
             {unoffending}] [ant: {offensive}]
     2: morally respectable or inoffensive; "a past that was
        scarcely savory" [syn: {savory}, {savoury}] [ant: {unsavory}]
     3: giving no offense; "a quiet inoffensive man"; "a refreshing
        inoffensive stimulant" [ant: {offensive}]
     4: of an inoffensive substitute for offensive terminology;
        "`peepee' is a common euphemistic term" [syn: {euphemistic}]
        [ant: {dysphemistic}]
     5: not offensive; "an inoffensive level" [syn: {uncontroversial}]
     6: causing no harm; "an inoffensive animal" [syn: {unoffending}]