IPA: /ˌkætəˈdaɪəptrɪk/
KK: /kætəˈdaɪəptrɪk/
Relating to a type of optical system that combines mirrors and lenses to focus light.
The catadioptric telescope provides a clearer image by using both lenses and mirrors.
Catadioptric → It is formed from "cata-" (from Greek "kata", meaning down or against) and "dioptrikos" (from Greek "dioptra", meaning to see through). The term refers to a system that uses both reflection and refraction to focus light, hence the combination of these elements.
Think of 'seeing through' ('dioptra') something that works 'down' or 'against' ('cata-') to focus light — that's what catadioptric means.