The Collaborative International Dictionary of English v.0.48:
Prismatic \Pris*mat"ic\, Prismatical \Pris*mat"ic*al\, a. [Cf.
1. Resembling, or pertaining to, a prism; as, a prismatic
form or cleavage.
2. Separated or distributed by a prism; formed by a prism;
as, prismatic colors.
3. (Crystallog.) Same as Orthorhombic.
Prismatic borax (Chem.), borax crystallized in the form of
oblique prisms, with ten molecules of water; --
distinguished from octahedral borax.
Prismatic colors (Opt.), the seven colors into which light
is resolved when passed through a prism; primary colors.
See Primary colors, under Color.
Prismatic compass (Surv.), a compass having a prism for
viewing a distant object and the compass card at the same
Prismatic spectrum (Opt.), the spectrum produced by the
passage of light through a prism.