We found 15 dictionaries that define the word in passing:

General (14 matching dictionaries)

1. in passing: Merriam-Webster
2. in passing: Oxford Learner's Dictionaries
3. in passing: Collins English Dictionary
4. in passing: Vocabulary.com
5. in passing: Cambridge Advanced Learner's Dictionary
6. in passing: Wiktionary
7. in passing: Dictionary.com
8. In passing: Wikipedia, the Free Encyclopedia
9. in passing: Rhymezone
10. in passing: FreeDictionary.org
11. in passing: Mnemonic Dictionary
12. in passing: TheFreeDictionary.com

Miscellaneous (1 matching dictionary)

13. in passing: Idioms

Definitions from WordNet (in passing) ▸ adverb:  incidentally; in the course of doing something else ("He made this remark in passing") Phrases: words said in passing, notice in passing, sounds heard in passing, mention in passing, pet a dog in passing, more... ▸ Words similar to in passing ▸ Usage examples for in passing ▸ Idioms related to in passing ▸ Wikipedia articles (New!) ▸ Words that often appear near in passing ▸ Rhymes of in passing ▸ Invented words related to in passing