1. Without illumination
   "the unilluminated side of Mars"
   - lightless, unlighted, unlit

See also: dark

• radian
• radiance
• radiancy
• radiant
• radiant energy
• radiant flux
• radiant heating
• radiantly
• radiate
• radiating
• radiatio optica
• radiation
• radiation diagram
• radiation field
• radiation pattern
• radiation pressure
• radiation pyrometer
• radiation sickness
• radiation syndrome
• radiation therapy
• radiative
• radiator
• radiator cap
• radiator grille
• radiator hose