A window installed primarily to let in light, often placed high on a wall, in a roof, or above a door. Covers skylights, dormer windows, and transom windows.
天窓 specifically refers to a skylight or roof window, while 明かり窓 is a broader term for any window designed to let in light, including transoms and dormer windows.
窓 is the general word for window, whereas 明かり窓 emphasizes the function of letting in light rather than providing a view or ventilation.
Etymology
Compound of 明かり (light) and 窓 (window). The exact historical derivation is uncertain, but the word transparently describes a window for letting in light.
