Subcaliber
Pronunciation : Sub*cal"i*ber
Part of Speech : a.
Definition : Defn: Smaller than the caliber of a firearm. [Written also subcalibre.] Subcaliber projectile, a projectile having a smaller diameter than the caliber of the arm from which it is fired, and to which it is fitted by means of a sabot. Knight.
Source : Webster's Unabridged Dictionary, 1913