ˌyu̇rənōˈpīˌlīt, -ˈnäpəˌlīt noun
( -s )
Etymology: German uranopilit, from uran- (II) + Greek pilos felt + German -it -ite — more at pile (hair)
: a mineral (UO 2 ) 6 (SO 4 )(OH) 10 .12H 2 O that is a hydrous basic sulfate of uranium and occurs in yellow velvety incrustations composed of microscopic needlelike crystals