Dictionary
Thesaurus
Medical
Scrabble®
Spanish Central
Browse DictionaryBrowse Thesaurus
Get our free apps!iPhone•iPad•Android
Games
Word of the Day
Video
Blog: Words at Play
My Faves
Dictionary

alt

abbreviation

Definition of ALT

1
alternate
2
altitude
3
alto
ADVERTISEMENT
Medical Dictionary

alt

abbreviation

Medical Definition of ALT

1
alternate
2
altitude

Learn More About ALT

Browse

7 ENTRIES FOUND:
  1. alt
  2. alt-country
  3. Alt key
  4. alt-pop
  5. alt-rock
  6. alt hor
  7. in alt
Next Word in the Dictionary: AltaPrevious Word in the Dictionary: alstroemeriaAll Words Near: alt
ADVERTISEMENT
10 Charming Words for Nasty People
Put-downs with flair
Learn More
When "Literally" isn't, well, literal
How to use a word that (literally) drives some people nuts.
Watch Now
Know what this is?
Test your vocab with our fun, fast game
Go Play
Fear of cats?
Ailurophobia, and 9 other unusual fears
Learn More
Join Us
Merriam-Webster
on Facebook
Merriam-Webster
on Twitter
Bookstore: Digital and Print
Merriam-Webster references for Mobile, Kindle, print, and more.
See All
Other Merriam-Webster Dictionaries