<p><strong>Noun:</strong></p><ul><li>The sign (,), a mark of punctuation used for indicating a division in a sentence, as in setting off a word, phrase, or clause, especially when such a division is accompanied by a slight pause or is to be noted in order to give order to the sequential elements of the sentence.</li><li>Used to separate items in a list.</li><li>Marks off thousands in numerals.</li><li>Separates types or levels of information in bibliographic and other data.</li><li>In many European countries, used as a decimal point.</li></ul><p><strong>Classical Prosody:</strong></p><ul><li>A fragment or smaller section of a colon.</li><li>The part of dactylic hexameter beginning or ending with the caesura.</li><li>The caesura itself.</li></ul><p><strong>Music:</strong></p><ul><li>The minute, virtually unheard difference in pitch between two enharmonic tones, as G♯ and A♭.</li></ul><p><strong>Biology:</strong></p><ul><li>Any of several nymphalid butterflies, including the North American Polygonia comma, having a comma-shaped silver mark on the underside of each hindwing.</li></ul><p><strong>End of Response</strong></p>