We found 13 dictionaries that define the word filename extension:

General (8 matching dictionaries)

1. filename extension: Vocabulary.com
2. filename extension: Wiktionary
3. filename extension: Dictionary.com
4. Filename extension: Wikipedia, the Free Encyclopedia
5. filename extension: Rhymezone
6. filename extension: FreeDictionary.org
7. filename extension: Mnemonic Dictionary
8. filename extension: TheFreeDictionary.com

Computing (3 matching dictionaries)

9. filename extension: Free On-line Dictionary of Computing
10. Filename Extension, filename extension: CCI Computer
11. filename extension: Encyclopedia

Medicine (1 matching dictionary)

12. online medical dictionary (No longer online)

Tech (1 matching dictionary)

13. Filename extension: Web Hosting Glossary

(Note: See filename_extensions as well.)

Definitions from Wiktionary (filename extension) ▸ noun:  (computing) Synonym of file extension. Similar: extension, format, long filename, file format, filetype, short filename, file size, file handle, file, .txt, more... Opposite: file prefix, file header, file identifier Adjectives: serial, manifest, near, noarch, intrinsic, extent, mainline, multiplatform, term, slab, core ▸ Words similar to filename extension ▸ Usage examples for filename extension ▸ Idioms related to filename extension ▸ Wikipedia articles (New!) ▸ Words that often appear near filename extension ▸ Rhymes of filename extension ▸ Invented words related to filename extension