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Synonyms

alt

1 American  
[alt] / ælt /

adjective

  1. high.


noun

  1. in alt, in the first octave above the treble staff.

alt- 2 American  
  1. variant of alti- before a vowel.

    altazimuth.


alt- 3 American  
  1. a combining form of alternative, used in compound words describing a nontraditional or unconventional version within a genre or category, often something provocative, subversive, or innovative: the alt-right movement; writers of alt-lit;

    alt-country bands;

    the alt-right movement;

    alt-weeklies;

    writers of alt-lit;

    quinoa and other alt-grains.


alt. 4 American  

abbreviation

  1. alteration.

  2. alternate.

  3. altitude.

  4. alto.


alt British  
/ ælt /

adjective

  1. (esp of vocal music) high in pitch

  2. of or relating to the octave commencing with the G above the top line of the treble staff

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. in the octave directly above the treble staff

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of alt1

1525–35; < Provençal < Latin altum, noun use of neuter of altus high

Origin of alt-3

First recorded in 1985–90; from the use of the prefix alt- in Usenet, to denote newsgroups with unconventional discussion topics

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Coachella has its own version of the Enchanted Tiki Room attraction from Disneyland — and it comes from the most unlikely of artists: British alt rockers Radiohead.

From Los Angeles Times • Apr. 13, 2026

JPMorgan’s action comes as multiple alt managers, including Blue Owl and BlackRock, have moved to limit investor withdrawals from certain private credit funds.

From Barron's • Mar. 11, 2026

Because this alt comedy makes no bones about its characters or situations being even remotely logical or realistic, anything goes — and does.

From Los Angeles Times • Feb. 27, 2026

Mark and Dahlia discuss this news, and also how lower court judges are calling out SCOTUS’ unreasoned, incoherent opinions and how some of the Justices are trying to control, alt, delete all the backbiting.

From Slate • Sep. 6, 2025

Some alt rock was blaring from her paint-covered Bose docking system.

From "The Last Olympian" by Rick Riordan