38, 39. Cover, protection, screen, shelter mean a defense against harm or danger and a provision for safety. The main idea in cover is that of concealment, as in darkness, in a wood, or behind something: The ground troops were left without cover when the air force was withdrawn. Screen refers especially to something behind which one can hide: A well-aimed artillery fire formed a screen for ground operations. Protection and shelter emphasize the idea of a guard or defense, a shield against injury or death. A protection is any such shield: In World War II, an air cover of airplanes served as a protection for troops. A shelter is something that covers over and acts as a place of refuge: An abandoned monastery acted as a shelter.

Did you mean cover-up?