We found 12 dictionaries that define the word in use:

General (9 matching dictionaries)

1. in use: Merriam-Webster
2. in use: Vocabulary.com
3. in-use, in use: Wordnik
4. in use: Wiktionary
5. In use, in use: Dictionary.com
6. in use: Rhymezone
7. in use: FreeDictionary.org
8. in use: Mnemonic Dictionary
9. in use: TheFreeDictionary.com

Business (1 matching dictionary)

10. In-use (vehicles): Energy Dictionary

Computing (1 matching dictionary)

11. in use: Encyclopedia

Miscellaneous (1 matching dictionary)

12. in use: Idioms

Definitions from WordNet (in use) ▸ adjective:  currently being used ("Robots are in use throughout industry") Opposite: unused, idle, vacant, available, unoccupied Types: popular, prevalent, widespread, ubiquitous, common, more... Phrases: value in use, English Grammar in Use, Data in use, It's in the Way That You Use It, Errors in early word use, more... ▸ Words similar to in use ▸ Usage examples for in use ▸ Idioms related to in use ▸ Wikipedia articles (New!) ▸ Popular nouns described by in use ▸ Words that often appear near in use ▸ Rhymes of in use ▸ Invented words related to in use