Source : Webster's Revised Unabridged Dictionary (1913)

Retread \Re*tread"\, v. t. & i.
   To tread again.

Source : WordNet®

retread
     n : a used automobile tire that has been remolded to give it new
         treads [syn: {recap}]
     v 1: use again in altered form; "retread an old plot" [syn: {rework},
           {make over}]
     2: give new treads to (a tire) [syn: {remold}, {remould}]