Cách sử dụng
Umbra refers to the darkest and deepest part of a shadow, where no light can reach. It is the area directly behind an object that is blocking light, which appears black or very dark. The word is commonly used in astronomical contexts, such as during a solar eclipse when the moon's shadow falls on the earth, and the area of complete darkness is called the umbra. Umbra can also be used metaphorically to describe something that is obscure, hidden, or mysterious.