faceplateEnglishOxford Dictionary of Englishfaceplate /ˈfeɪspleɪt / ▸ noun 1 a plate protecting a piece of machinery, a light switch, or an electrical outlet. 2 an enlarged end or attachment on the end of the mandrel on a lathe, with slots and holes on which work can be mounted. 3 the transparent window of a diver's or astronaut's helmet. 4 the part of a cathode ray tube that carries the phosphor screen.