means A tall tower on or near a coast that shines a powerful light to warn ships of dangerous rocks, shallows, or the shore itself.

from A plain English compound, transparent as its own beam: "light" plus "house," both ancient Germanic words. The word arrives late and obvious — once people built houses specifically to hold a great light, they simply nailed the two together. The Old English "lēoht" (light) traces back to a Proto-Indo-European root *leuk-, "to shine," the same glow that lights up Latin "lux" and Greek "leukos" (white). "House" is humble Germanic "hūs," a dwelling — though no one was ever meant to live cozily here, only to keep the flame fed and burning.