We found 11 dictionaries that define the word knock-knees:

General (7 matching dictionaries)

1. knock-knees: Merriam-Webster
2. knock-knees, knock-knees: Collins English Dictionary
3. knock-knees: Wordnik
4. knock-knees: Wiktionary
5. knock-knees: Dictionary.com
6. knock-knees: FreeDictionary.org
7. knock-knees: TheFreeDictionary.com

Medicine (4 matching dictionaries)

8. knock-knees: Merriam-Webster Medical Dictionary
9. Knock-knees: MedTerms.com Medical Dictionary
10. online medical dictionary (No longer online)
11. Knock-knees: Drug Medical Dictionary

(Note: See knock-knee as well.)

Definitions from Wiktionary (Knock-knee) ▸ noun:  Alternative form of knock knee [The medical condition genu valgum.] ▸ Also see knock-knee Opposite: bow-legged, genu varum, bandy-legged ▸ Words similar to knock-knees ▸ Usage examples for knock-knees ▸ Idioms related to knock-knees ▸ Wikipedia articles (New!) ▸ Popular adjectives describing knock-knees ▸ Words that often appear near knock-knees ▸ Rhymes of knock-knees ▸ Invented words related to knock-knees