Definition of rugate in US English:

rugate

adjective

  • 1Botany and Zoology. Characterized by wrinkles or ridges; wrinkled.

  • 2Optics. Of a filter, coating, etc.: having a refractive index which varies smoothly in a regular, typically sinusoidal, manner with depth.

Origin

Mid 19th century; earliest use found in James Dana (1813–1895), geologist, zoologist, and teacher. From classical Latin rūgātus having a wrinkled surface from rūga + -ātus.

Pronunciation

rugate

/ˈruːɡeɪt/