Source : Webster's Revised Unabridged Dictionary (1913)

Complimentary \Com`pli*men"ta*ry\, a.
   Expressive of regard or praise; of the nature of, or
   containing, a compliment; as, a complimentary remark; a
   complimentary ticket. ``Complimentary addresses.''
   --Prescott.

Source : WordNet®

complimentary
     adj 1: conveying or resembling a compliment; "a complimentary
            remark" [ant: {uncomplimentary}]
     2: costing nothing; "complimentary tickets" [syn: {costless}, {free},
         {gratis(p)}, {gratuitous}]