Source : Webster's Revised Unabridged Dictionary (1913)

Tinny \Tin"ny\, a.
   Pertaining to, abounding with, or resembling, tin. ``The
   tinny strand.'' --Drayton.

Source : WordNet®

tinny
     adj 1: of very poor quality [syn: {bum}, {cheap}, {cheesy}, {chintzy},
             {crummy}, {punk}, {sleazy}]
     2: thin and metallic in sound; lacking resonance; "an
        unpleasant tinny voice"
     [also: {tinniest}, {tinnier}]