actinometer Syllabification: (ac·ti·nom·e·ter)Pronunciation: /ˌaktəˈnämitər/Definition of actinometer noun Physics an instrument for measuring the intensity of radiation, typically ultraviolet radiation. Origin: mid 19th century: from Greek aktis, aktin- 'ray' + -meteractinometer in other Oxford dictionaries Definition of actinometer in the British & World English dictionary
