Altair Syllabification: (Al·tair)Pronunciation: /ˈalˌte(ə)r, -ˌtī(ə)r, alˈtī(ə)r, -ˈte(ə)r/ AstronomyDefinition of Altair the brightest star in the constellation Aquila. Origin:Arabic, literally 'flying eagle'Altair in other Oxford dictionaries Definition of Altair in the British & World English dictionary