Breadcrumb Home > Dictionary > Index A alt: Meaning and Definition of Find definitions for: alt Pronunciation: (alt) [key] — Music. Music. —adj. high. —n. in the first octave above the treble staff. alt- Pronunciation: [key] var. ofbefore a vowel: altazimuth. alt. Pronunciation: [key] alteration. alternate. altitude. alto. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: alt (Thesaurus) Alston Alta. TrendingHere are the facts and trivia that people are buzzing about. Biographies: Notable Jewish Religious Leaders Current Events This Week: September 2023 Hispanic Population and the 2010 U.S. Census Preamble of the United Nations Charter The Jewish Calendar ✖ Related Content Daily Word Quiz: parallax Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language