[{"word":"greywacke","phonetic":"/ˈɡɹeɪwakə/","phonetics":[{"text":"/ˈɡɹeɪwakə/","audio":""}],"meanings":[{"partOfSpeech":"noun","definitions":[{"definition":"A hard dark sandstone with poorly sorted angular grains of quartz, feldspar, and small rock fragments in a compact, clay-fine matrix.","synonyms":[],"antonyms":[]}],"synonyms":[],"antonyms":[]}],"license":{"name":"CC BY-SA 3.0","url":"https://creativecommons.org/licenses/by-sa/3.0"},"sourceUrls":["https://en.wiktionary.org/wiki/greywacke"]}]