We found 25 dictionaries that define the word lights out:

General (19 matching dictionaries)

1. lights out: Longman Dictionary of Contemporary English
2. lights-out, lights out: Merriam-Webster
3. lights out: Oxford Learner's Dictionaries
4. lights out: American Heritage Dictionary of the English Language
5. lights-out, lights-out, lights out: Collins English Dictionary
6. Lights-Out, lights-out: Wordnik
7. lights-out: Cambridge Advanced Learner's Dictionary
8. lights-out, lights out: Wiktionary
9. lights out: The Wordsmyth English Dictionary-Thesaurus
10. lights out: Infoplease Dictionary
11. lights-out, lights out: Dictionary.com
12. Lights Out (Antimatter album), Lights Out (Breaking Benjamin song), Lights Out (Clifford the Big Red Dog), Lights Out (Glee), Lights Out (Go Crazy), Lights Out (Graveyard album), Lights Out (Ingrid Michaelson album), Lights Out (Lil Wayne album), Lights Out (P.O.D. song), Lights Out (Peter Wolf album), Lights Out (Rick Astley song), Lights Out (Royal Blood song), Lights Out (Santigold song), Lights Out (Silverline album), Lights Out (Sugarcult album), Lights Out (UFO album), Lights Out (antimatter), Lights Out (film), Lights Out (game), Lights Out (manhwa), Lights Out (radio show), Lights Out (video game), Lights Out, Lights Out, Lights out (manufacturing), Lights out, The Lights Out: Wikipedia, the Free Encyclopedia
13. lights-out: Rhymezone
14. lights-out: FreeDictionary.org
15. lights-out: Mnemonic Dictionary
16. lights-out, lights out: TheFreeDictionary.com
17. lights-out: Vocabulary.com

Business (1 matching dictionary)

18. lights out: Legal dictionary

Computing (1 matching dictionary)

19. lights out: Encyclopedia

Medicine (1 matching dictionary)

20. lights out: Medical dictionary

Miscellaneous (1 matching dictionary)

21. lights out: Idioms

Science (1 matching dictionary)

22. A Glossary of Mathematical Terms (No longer online)

Slang (1 matching dictionary)

23. Lights Out, lights out: Urban Dictionary

Definitions from Wiktionary (lights out) ▸ noun:  Unconsciousness. ▸ noun:  Alternative form of lights-out [The time at night at which artificial lights are to be turned off, a curfew or bedtime.] Similar: Taps, blackout, blankout, unconsciousness, nonconsciousness, lights-out, pitch darkness, unillumination, unsleep, coma, more... Opposite: lights on, illuminated, brightened, lit up Phrases: punch lights out, punch someone's lights out, punch someones lights out, punched lights out, punches lights out, more... ▸ Words similar to lights out ▸ Usage examples for lights out ▸ Idioms related to lights out ▸ Wikipedia articles (New!) ▸ Words that often appear near lights out ▸ Rhymes of lights out ▸ Invented words related to lights out