As an adjective rectangular
is having a shape like a rectangle.
As a noun viewport is
viewport.
rectangular
English
Adjective
(head)
Having a shape like a rectangle.
Having axes that meet each other with right angles.
viewport
English
Noun
(
en noun)
(computer graphics) A rectangular region representing the range or area currently being viewed.
A viewing window.
- acrylic plastic viewports in pressure vessels for human occupancy