aphanite
ap·ha·nite
noun
1.
fine-grained homogeneous rock (such as basalt) containing minerals undetectable by the naked eye
Origin
From Ancient Greek ἀφανής (aphanḗs, “indistinct, unseen, obscure”) + English -ite.
Related words
Broader terms
WordNet 2.1 (Princeton University). Wiktionary (CC BY-SA). WordNet 2.1 Copyright Princeton University. All rights reserved. Wiktionary content is available under the Creative Commons Attribution-ShareAlike Licence.