Source : Webster's Revised Unabridged Dictionary (1913)

Thimbleberry \Thim"ble*ber`ry\, n. (Bot.)
   A kind of black raspberry ({Rubus occidentalis}), common in
   America.

Source : WordNet®

Rubus occidentalis
     n : raspberry native to eastern North America having black
         thimble-shaped fruit [syn: {black raspberry}, {blackcap},
          {blackcap raspberry}, {thimbleberry}]