plagiogranite
/ˌpleɪdʒɪəˈɡranɪt/Geology
noun
Any of a range of granitic rocks, occurring particularly in ophiolites, which are low in potassium and rich in sodic plagioclase feldspar.
Origin
1950s; earliest use found in Bulletin Volcanologique. From plagio- + granite, after Russian plagiogranit (N. Khrushchev 1931, in Trans. Geol. & Prospecting Service U.S.S.R. 90 16; shortened from German Plagioklasgranit.