andalusitePronunciation: /ˌandəˈluːsʌɪt/Definition of andalusite noun [mass noun] a grey, green, brown, or pink aluminosilicate mineral occurring mainly in metamorphic rocks as elongated rhombic prisms, sometimes of gem quality. Origin: early 19th century: from the name of the Spanish region of Andalusia + -ite1andalusite in other Oxford dictionaries Definition of andalusite in the US English dictionary