11 letters · 20 points in Scrabble
noun a metamorphic rock composed chiefly of amphibole and plagioclase
originEtymology tree English amphibole Proto-Indo-European *-tósder. Ancient Greek -της (-tēs)der. Ancient Greek -ῑ́της (-ī́tēs)der. Latin -ītēsbor. French -iteder. English -ite English amphibolite From amphibole + -ite.
Etymology from Wiktionary, CC BY-SA 3.0