nephˈōgraph /-gräf/ noun

An instrument for photographing clouds in order to determine their position

nephologic /-ə-lojˈ/ or nephologˈical adjective

nepholˈogist noun

nephology /nef-olˈə-ji/ noun

The study of clouds in meteorology

nephˈōscope noun

An apparatus which determines the direction and velocity of movement of clouds