We found 14 dictionaries that define the word capital letters:

General (6 matching dictionaries)

1. capital letters: Vocabulary.com
2. capital letters: Cambridge Advanced Learner's Dictionary
3. capital letters: Wiktionary
4. capital letters: Dictionary.com
5. Capital Letters (song), Capital letters: Wikipedia, the Free Encyclopedia
6. Capital letters: TheFreeDictionary.com

Art (1 matching dictionary)

7. Capital Letters: Glossary of English Grammar Terms

Business (2 matching dictionaries)

8. Capital letters: Legal dictionary
9. Capital letters: Financial dictionary

Computing (1 matching dictionary)

10. Capital letters: Encyclopedia

Medicine (1 matching dictionary)

11. Capital letters: Medical dictionary

Miscellaneous (1 matching dictionary)

12. Capital letters: Idioms

Science (1 matching dictionary)

13. capital letters: LITTLE EXPLORERS(TM) Picture Dictionary

Slang (1 matching dictionary)

14. capital letters: Urban Dictionary

(Note: See capital_letter as well.)

Definitions from Wiktionary (capital letter) ▸ noun:  An upper-case letter (A, B, C, ... as opposed to a, b, c, ...), used for emphasis, for starting sentences and proper names, etc. ▸ Also see capital_letter Types: A, B, C, D, E, F, G, H, I, J, more... Phrases: small capital letters, in capital letters, more... ▸ Words similar to capital letters ▸ Usage examples for capital letters ▸ Idioms related to capital letters ▸ Wikipedia articles (New!) ▸ Words that often appear near capital letters ▸ Rhymes of capital letters ▸ Invented words related to capital letters