microdioriteWiktionary 原文英美构词拆解micromicro-前缀dioritediorite词干micro-(diminutive) Very small. · (metric units) One millionth.词源说明From micro- + diorite.释义名词noun1(geology) A course-grained igneous rock, of volcanic origin, containing mostly plagioclase feldspar; a rock whose composition is intermediate between andesite and diorite.