We found 17 dictionaries that define the word many happy returns:

General (12 matching dictionaries)

1. many happy returns: Longman Dictionary of Contemporary English
2. many happy returns: Merriam-Webster
3. many happy returns: Oxford Learner's Dictionaries
4. Many happy returns, many happy returns: Collins English Dictionary
5. many happy returns (of the day): Cambridge Advanced Learner's Dictionary
6. many happy returns: Wiktionary
7. many happy returns: Dictionary.com
8. Many Happy Returns (Person of Interest), Many Happy Returns (Prisoner episode), Many Happy Returns (Sherlock), Many Happy Returns (TV series), Many Happy Returns (The Prisoner), Many Happy Returns (disambiguation), Many happy returns (greeting): Wikipedia, the Free Encyclopedia
9. Many Happy Returns: TheFreeDictionary.com
10. Many happy returns: Phrase Finder

Business (2 matching dictionaries)

11. Many Happy Returns: Legal dictionary
12. Many Happy Returns: Financial dictionary

Computing (1 matching dictionary)

13. Many Happy Returns: Encyclopedia

Miscellaneous (1 matching dictionary)

14. Many Happy Returns: Idioms

Slang (1 matching dictionary)

15. Many happy returns: Urban Dictionary

Definitions from Wiktionary (many happy returns) ▸ noun:  (idiomatic) A greeting, usually for birthdays, in reference to the passing year; Happy birthday! Similar: Jubilee, year of our Lord, golden jubilee, yearday, yearful, eighteenth, yearer, a year and a day, twenty-first, term of years, more... Opposite: farewell, goodbye, adieu Phrases: many happy returns of the day, more... ▸ Words similar to many happy returns ▸ Usage examples for many happy returns ▸ Idioms related to many happy returns ▸ Wikipedia articles (New!) ▸ Words that often appear near many happy returns ▸ Rhymes of many happy returns ▸ Invented words related to many happy returns