Source : Webster's Revised Unabridged Dictionary (1913)

Testimonial \Tes`ti*mo"ni*al\, n. [Cf. OF. testimoniale, LL.
   testimonialis, L. testimoniales (sc. litter[ae]). See
   {Testimonial}, a.]
   1. A writing or certificate which bears testimony in favor of
      one's character, good conduct, ability, etc., or of the
      value of a thing.

   2. Something, as money or plate, presented to a preson as a
      token of respect, or of obligation for services rendered.

Testimonial \Tes`ti*mo"ni*al\, a. [L. testimonialis: cf. F.
   testimonial.]
   Relating to, or containing, testimony.

Source : WordNet®

testimonial
     n 1: something that serves as evidence; "his effort was testimony
          to his devotion" [syn: {testimony}]
     2: something given or done as an expression of esteem [syn: {tribute}]
     3: something that recommends (or expresses commendation) of a
        person or thing as worthy or desirable [syn: {recommendation},
         {good word}]

testimonial
     adj 1: expressing admiration or appreciation; "testimonial dinner"
     2: of or relating to or constituting testimony