early 15c., "crescent-shaped;" 1620s, "pertaining to the moon," from Old French lunaire (15c.), from Latin lunaris "of the moon," from luna "moon" (see luna).
Entries linking to lunar
luna n.
late 14c. "the moon," especially as personified in a Roman goddess answering to Greek Selene; also an alchemical name for "silver;" from Latin luna "moon, goddess of the moon," from PIE *leuksna- (source also of Old Church Slavonic luna "moon," Old Prussian lauxnos "stars," Middle Irish luan "light, moon"), suffixed form of root *leuk- "light, brightness." The luna moth (1841, American English) so called for the crescent-shaped eye-spots on its wings.
*leuk-
Proto-Indo-European root meaning "light, brightness."
It forms all or part of: allumette; elucidate; illumination; illustration; lea; leukemia; leuko-; light (n.) "brightness, radiant energy;" lightning; limn; link (n.2) "torch of pitch, tow, etc.;" lucent; lucid; Lucifer; luciferase; luciferous; lucifugous; lucubrate; lucubration; luculent; lumen; Luminal; luminary; luminate; luminescence; luminous; luna; lunacy; lunar; Lunarian; lunate; lunation; lunatic; lune; lunette; luni-; luster; lustrum; lux; pellucid; sublunary; translucent.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit rocate "shines;" Armenian lois "light," lusin "moon;" Greek leukos "bright, shining, white;" Latin lucere "to shine," lux "light," lucidus "clear;" Old Church Slavonic luci "light;" Lithuanian laukas "pale;" Welsh llug "gleam, glimmer;" Old Irish loche "lightning," luchair "brightness;" Hittite lukezi "is bright;" Old English leht, leoht "light, daylight; spiritual illumination," German Licht, Gothic liuhaþ "light."