What is delta-shaped?

Delta-shaped refers to the triangular or delta-shaped configuration of objects or structures. It is often used to describe the wing shape of some aircraft, where the wings are positioned in a triangular shape resembling the Greek letter delta. This design is popular in supersonic and high-speed aircraft because it provides a greater lift and reduces drag. Delta-shaped objects can also be found in various natural and man-made structures, such as river deltas, pyramids, and some bridges. Additionally, delta waves are a type of brain wave that is associated with deep sleep.