ˈandəˌzīt noun
( -s )
Etymology: German andesit, from Andes, its locality + German -it -ite
: an extrusive usually dark grayish rock consisting essentially of oligoclase or andesine feldspar with augite, hornblende, hypersthene, or biotite
• an·de·sit·ic |andə|zid.ik adjective