Source : Webster's Revised Unabridged Dictionary (1913)

Carbonate \Car"bon*ate\, n. [Cf. F. carbonate.] (Chem.)
   A salt or carbonic acid, as in limestone, some forms of lead
   ore, etc.

Source : WordNet®

carbonate
     n : a salt or ester of carbonic acid (containing the anion CO3)
     v 1: treat with carbon dioxide; "Carbonated soft drinks"
     2: turn into a carbonate