noun
top light; skylight; roof light
Refers to a light source or window positioned at the top of a space, such as a skylight in architecture or a top-mounted light in photography/design.
この部屋にはトップライトがあって、昼間はとても明るい。
This room has a skylight, so it's very bright during the day.
写真スタジオでは、
In a photo studio, they sometimes use a top light to illuminate the subject.