HORNFELS Meaning of HORNFELS in English [ 'hɔ:nfɛlz ]■ noun a dark, fine-grained metamorphic rock consisting largely of quartz, mica, and feldspars.OriginC19: from Ger., lit. 'horn rock'. Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004