We found 30 dictionaries that define the word usn:

General (21 matching dictionaries)

1. usn: Longman Dictionary of Contemporary English
2. USN, USN: Merriam-Webster
3. USN: Oxford Learner's Dictionaries
4. USN: American Heritage Dictionary of the English Language
5. USN: Collins English Dictionary
6. USN: Vocabulary.com
7. usn: Wordnik
8. the USN, the usn: Cambridge Advanced Learner's Dictionary
9. USN: Webster's New World College Dictionary, 4th Ed.
10. USN: The Wordsmyth English Dictionary-Thesaurus
11. USN: Infoplease Dictionary
12. USN(RET), USN, u.s.n: Dictionary.com
13. USN (disambiguation), USN: Wikipedia, the Free Encyclopedia
14. Usn: Rhymezone
15. USN: Stammtisch Beau Fleuve Acronyms
16. usn: FreeDictionary.org
17. usn: Mnemonic Dictionary
18. USN: TheFreeDictionary.com
19. USN: Wiktionary

Business (1 matching dictionary)

20. USN: bizterms.net

Computing (1 matching dictionary)

21. USN: Encyclopedia

Miscellaneous (3 matching dictionaries)

22. USN, USN, USN: Terminology and Descriptions of Geneaological Words
23. USN(RET), USN: Acronym Finder
24. AbbreviationZ (No longer online)

Science (1 matching dictionary)

25. Glossary of Roots of Botanical Names (No longer online)

Slang (1 matching dictionary)

26. USN (University School of Nashville), USN: Urban Dictionary

Tech (2 matching dictionaries)

27. USN: GEOGRAPHIC INFORMATION SYSTEMS, CARTOGRAPHY, AND REMOTE SENSING
28. DOD Dictionary of Military Terms: Joint Acronyms and Abbreviations (No longer online)

(Note: See usns as well.)

Definitions from Wiktionary (USN) ▸ noun:  Initialism of United States Navy. ▸ noun:  (computing, Microsoft Windows) Initialism of update sequence number. Similar: destroyer escort, Seabee, USAF, Naval, LtCol, air force, Nimitz, marine corps, submarine, air commodore, more... Opposite: them, others, non-US Types: Navy, Army, Air Force, Marines, Coast Guard, more... Phrases: the usn, USN Journal, usn rank, usn officer, bleached by the usn, more... ▸ Words similar to usn ▸ Usage examples for usn ▸ Idioms related to usn ▸ Wikipedia articles (New!) ▸ Popular adjectives describing usn ▸ Words that often appear near usn ▸ Rhymes of usn ▸ Invented words related to usn