sur•vey•orPronunciation: (sur-vA\u0027ur), [key] —n. 1. a person whose occupation is surveying. 2. an overseer or supervisor. 3. Chiefly Brit.a person who inspects something officially for the purpose of ascertaining condition, value, etc. 4. (formerly) a U.S. customs official responsible for ascertaining the quantity and value of imported merchandise. 5. (cap.) U.S. Aerospace.one of a series of space probes (1966–68) that analyzed lunar soil and obtained other scientific information after soft-landing on the moon.