[{"word":"sigma","phonetic":"/ˈsɪɡmə/","phonetics":[{"text":"/ˈsɪɡmə/","audio":"https://api.dictionaryapi.dev/media/pronunciations/en/sigma-us.mp3","sourceUrl":"https://commons.wikimedia.org/w/index.php?curid=36786769"}],"meanings":[{"partOfSpeech":"noun","definitions":[{"definition":"The eighteenth letter of the Classical and Modern Greek alphabets, the twentieth letter of Old and Ancient.","synonyms":[],"antonyms":[]},{"definition":"The symbol Σ, used to indicate summation of a set or series.","synonyms":[],"antonyms":[]},{"definition":"The symbol σ, used to indicate one standard deviation from the mean, particularly in a normal distribution.","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/sigma"]}]