|hīə(ˌ)lōˌpī|lid.ik adjective
Etymology: International Scientific Vocabulary hyalopilit- (from German hyalopilitisch hyalopilitic, from hyal- + Greek pilos felt + German -it -ite + -isch -ish, from Old High German -isc ) + -ic — more at pile (hair)
: composed of or characterized by innumerable slender microlites embedded in glass
hyalopilitic structure is frequently found in basic lavas