Entry 1 sense Webster, 1913 Dolerite · Dol·er·ite · IPA /ˈdɑl.əˌɹaɪt/ 01 n. A dark, crystalline, igneous rock, chiefly pyroxene with labradorite. 1. A dark, crystalline, igneous rock, chiefly pyroxene with labradorite.(Petrography)