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A dense, homogeneous rock with constituents so fine that they cannot be seen by the naked eye.

[From Greek aphanēs, unseen : a-, not; see a-1 + phainesthai, phan-, to appear, passive of phainein, to show; see phenomenon.]

aph′a·nit′ic (-nĭt′ĭk) adj.


(Geological Science) any fine-grained rock, such as a basalt, containing minerals that cannot be distinguished with the naked eye
[C19: from Greek aphanēs invisible]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.aphanite - fine-grained homogeneous rock (such as basalt) containing minerals undetectable by the naked eye
rock, stone - material consisting of the aggregate of minerals like those making up the Earth's crust; "that mountain is solid rock"; "stone is abundant in New England and there are many quarries"
References in periodicals archive ?
At San Diego, silica flooding and hairline quartz veinlets obscure breccated aphanitic rock in four outcrops that protrude through shallow soil and elluvial cover over a 20 x 30 meter area.