A flash of light; a spark.
The twinkling of a star or other celestial body caused by turbulence in the Earth's atmosphere.
The flash of light produced by something (especially a phosphor) when it absorbs ionizing radiation.
Light from above; toplighting.
Any glazing above a main window, partition or door
A skylight.
The upper (and usually smaller) part (casement) of a window, often hinged a the top