horologyPronunciation: /hɒˈrɒlədʒi/Definition of horology noun [mass noun] 1the study and measurement of time. 2the art of making clocks and watches. Derivatives horologer noun horologicalPronunciation: /hɒrəˈlɒdʒɪk(ə)l/ adjective horologist noun Origin: early 19th century: from Greek hōra 'time' + -logyhorology in other Oxford dictionaries Definition of horology in the US English dictionary