We found 20 dictionaries that define the word hard hat:

General (17 matching dictionaries)

1. hard hat: Merriam-Webster
2. hard hat: Oxford Learner's Dictionaries
3. hard-hat, hard hat: Collins English Dictionary
4. hard hat: Vocabulary.com
5. hard-hat: Wordnik
6. hard hat: Cambridge Advanced Learner's Dictionary
7. hard hat: Wiktionary
8. hard-hat, hard hat: The Wordsmyth English Dictionary-Thesaurus
9. hard hat: Infoplease Dictionary
10. hard-hat, hard hat: Dictionary.com
11. Hard hat: Wikipedia, the Free Encyclopedia
12. hard hat: Rhymezone
13. hard hat: FreeDictionary.org
14. hard hat: Mnemonic Dictionary
15. hard-hat, hard hat: TheFreeDictionary.com
16. hard hat: Longman Dictionary of Contemporary English

Computing (1 matching dictionary)

17. hard-hat, hard hat: Encyclopedia

Slang (1 matching dictionary)

18. Hard Hat, The Hard Hat: Urban Dictionary

Tech (1 matching dictionary)

19. Oil and Gas Well Drilling and Servicing eTool (No longer online)

(Note: See hard_hats as well.)

Definitions from Wiktionary (hard hat) ▸ noun:  A helmet, usually made from rigid plastic, used on construction sites to protect the head from falling objects. Similar: tin hat, safety hat, hardhat, construction helmet, safety helmet, crash-helmet, helm, helmette, Hatt, head dress, more... Opposite: soft hat, safety helmet, protective headgear Types: baseball cap, bump cap, full brim, mining, welding, logging, construction, more... Phrases: Hard Hat Riot, Hard Hat Area, more... Adjectives: tricorn, flat, strawhat, brim, hatty, superfrontal, solitaire, bicorn, hatted, hood, caped ▸ Words similar to hard hat ▸ Usage examples for hard hat ▸ Idioms related to hard hat ▸ Wikipedia articles (New!) ▸ Words that often appear near hard hat ▸ Rhymes of hard hat ▸ Invented words related to hard hat