(also photo·cell ) noun
an electric device that uses a stream of light. When the stream is broken it shows that sb/sth is present, and can be used to control alarms, machinery, etc.
(also photo·cell ) noun
an electric device that uses a stream of light. When the stream is broken it shows that sb/sth is present, and can be used to control alarms, machinery, etc.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005