The Collaborative International Dictionary
Aphanitic
Aphanitic \Aph`a*nit"ic\, a. (Min.) Resembling aphanite; having a very fine-grained structure. [1913 Webster] ||
Wiktionary
aphanitic
a. (context geology English) Pertaining to or consisting of aphanites, igneous rocks which have crystals too fine to be seen by the naked eye.
WordNet
aphanitic
adj. of or relating to aphanite