Source : Webster's Revised Unabridged Dictionary (1913)

Spearmint \Spear"mint`\, n. [So named from its spiry, not
   capitate, inflorescence. --Dr. Prior.] (Bot.)
   A species of mint ({Mentha viridis}) growing in moist soil.
   It vields an aromatic oil. See {Mint}, and {Mentha}.