Gyroidal
Pronunciation : Gy*roid"al
Part of Speech : a.
Etymology : [Gr. -oid + -al.]
Definition : 1. Spiral in arrangement or action.
2. (Crystallog.)
Defn: Having the planes arranged spirally, so that they incline all to the right (or left) of a vertical line; -- said of certain hemihedral forms.
3. (Opt.)
Defn: Turning the plane of polarization circularly or spirally to the right or left.
Source : Webster's Unabridged Dictionary, 1913