Source : Webster's Revised Unabridged Dictionary (1913)

Dentil \Den"til\, n. [LL. dentillus, for L. denticulus. Cf.
   {Dentelli}, {Denticle}, {Dentile}.] (Arch.)
   A small square block or projection in cornices, a number of
   which are ranged in an ornamental band; -- used particularly
   in the Ionic, Corinthian, and Composite orders.