We found 26 dictionaries that define the word hard on:

General (20 matching dictionaries)

1. hard-on: Merriam-Webster
2. hard-on, hard on: Oxford Learner's Dictionaries
3. hard-on: American Heritage Dictionary of the English Language
4. hard-on, hard-on: Collins English Dictionary
5. hard-on: Vocabulary.com
6. hard-on: Wordnik
7. hard-on: Cambridge Advanced Learner's Dictionary
8. hard-on, hard on: Wiktionary
9. hard-on: Webster's New World College Dictionary, 4th Ed.
10. hard-on: The Wordsmyth English Dictionary-Thesaurus
11. hard-on: Infoplease Dictionary
12. hard-on, hard on: Dictionary.com
13. Hard On (video compilation), Hard on: Wikipedia, the Free Encyclopedia
14. hard-on: Rhymezone
15. hard-on: FreeDictionary.org
16. hard-on: Mnemonic Dictionary
17. Hard on, hard-on: TheFreeDictionary.com
18. hard on: Longman Dictionary of Contemporary English

Business (1 matching dictionary)

19. Hard on, hard-on: Legal dictionary

Computing (1 matching dictionary)

20. Hard on, hard-on: Encyclopedia

Medicine (1 matching dictionary)

21. Hard on, hard-on: Medical dictionary

Miscellaneous (1 matching dictionary)

22. hard on: Idioms

Slang (2 matching dictionaries)

23. hard-on: English slang and colloquialisms used in the United Kingdom
24. American-Australian Slang Dictionary (No longer online)

Definitions from Wiktionary (Hard on) ▸ noun:  Alternative form of hard-on [(slang, vulgar) An erection of the penis.] Similar: erection, Hardon, stiffie, hardass, hate boner, hard man, hateboner, strap on, shlong, cockstand, more... Opposite: soft on, lenient towards, forgiving of Phrases: been hard on, being hard on, is hard on, puts the hard word on, putting the hard word on, more... Adjectives: pussy, three-legged, wick, ding-dong, outie, crank, cavalier, hung, wood, willy, well hung ▸ Words similar to hard on ▸ Usage examples for hard on ▸ Idioms related to hard on ▸ Wikipedia articles (New!) ▸ Words that often appear near hard on ▸ Rhymes of hard on ▸ Invented words related to hard on