We found 27 dictionaries that define the word on-line:

General (15 matching dictionaries)

1. on-line: Collins English Dictionary
2. on-line: Vocabulary.com
3. On-Line, On-line, on-line: Wordnik
4. on-line: Cambridge Advanced Learner's Dictionary
5. on-line: Wiktionary
6. on-line: The Wordsmyth English Dictionary-Thesaurus
7. on-line: Infoplease Dictionary
8. on-line: Dictionary.com
9. on-line: Cambridge Essential American English Dictionary
10. On-line: Wikipedia, the Free Encyclopedia
11. on-line: Rhymezone
12. on-line: AllWords.com Multi-Lingual Dictionary
13. on-line: FreeDictionary.org
14. on-line: Mnemonic Dictionary
15. on-line: TheFreeDictionary.com

Art (4 matching dictionaries)

16. English-Chinese Dictionary of Graphic Communications (Big 5) (No longer online)
17. Movie Terminology Glossary (No longer online)
18. On-Line: A Cross Reference of Latin and Greek Elements
19. On-line: Lexicon of Linguistics

Computing (5 matching dictionaries)

20. on-line: Free On-line Dictionary of Computing
21. on-line: CCI Computer
22. Internet Terms (No longer online)
23. I T Glossary (No longer online)
24. on-line: Encyclopedia

Medicine (2 matching dictionaries)

25. online medical dictionary (No longer online)
26. on-line: Medical dictionary

Tech (1 matching dictionary)

27. AUTOMOTIVE TERMS (No longer online)

Definitions from WordNet (on-line) ▸ adjective:  connected to a computer network or accessible by computer ("An on-line database") ▸ adjective:  on a regular route of a railroad or bus or airline system ("On-line industries") Similar: current, connected, machine-accessible, off-line, on-screen, deconnected, gasfired, on-stage, on-time, energised, more... Opposite: offline, disconnected, not connected, unconnected Types: internet, e-mail, World Wide Web, intranet, extranet, more... Phrases: on-line database, on-line transaction processing, imago on-line, internex on-line, on-line analytical processing, more... Colors:     blue,     green,     red,     yellow,     orange, more... ▸ Words similar to on-line ▸ Usage examples for on-line ▸ Idioms related to on-line ▸ Wikipedia articles (New!) ▸ Popular nouns described by on-line ▸ Words that often appear near on-line ▸ Rhymes of on-line ▸ Invented words related to on-line