We found 39 dictionaries that define the word hardening:

General (22 matching dictionaries)

1. hardening: Merriam-Webster
2. hardening: American Heritage Dictionary of the English Language
3. hardening: Collins English Dictionary
4. hardening: Vocabulary.com
5. Hardening, hardening: Wordnik
6. hardening: Cambridge Advanced Learner's Dictionary
7. hardening: Wiktionary
8. hardening: Webster's New World College Dictionary, 4th Ed.
9. hardening: Infoplease Dictionary
10. hardening: Dictionary.com
11. hardening: Cambridge Essential American English Dictionary
12. Hardening (botany), Hardening (computing), Hardening (metallurgy), Hardening: Wikipedia, the Free Encyclopedia
13. Hardening: Online Plain Text English Dictionary
14. hardening: Webster's Revised Unabridged, 1913 Edition
15. hardening: Rhymezone
16. Hardening: AllWords.com Multi-Lingual Dictionary
17. hardening: Webster's 1828 Dictionary
18. hardening: FreeDictionary.org
19. hardening: Mnemonic Dictionary
20. hardening: TheFreeDictionary.com

Art (1 matching dictionary)

21. Glossary of Stamp Collecting Terms (No longer online)

Business (5 matching dictionaries)

22. Hardening: bizterms.net
23. Construction Term Glossary (No longer online)
24. Hardening: Investopedia
25. hardening: Legal dictionary
26. BusinessDictionary.com (No longer online)

Computing (3 matching dictionaries)

27. hardening: Computer Telephony & Electronics Dictionary and Glossary
28. Technopedia (No longer online)
29. hardening: Encyclopedia

Medicine (3 matching dictionaries)

30. hardening: Merriam-Webster Medical Dictionary
31. Dorland's Illustrated Medical Dictionary (No longer online)
32. hardening: Medical dictionary

Miscellaneous (1 matching dictionary)

33. hardening: Idioms

Science (1 matching dictionary)

34. Botanical Terms (No longer online)

Tech (3 matching dictionaries)

35. Metal Terminology (No longer online)
36. AUTOMOTIVE TERMS (No longer online)
37. Glossary of Fastener Terms (No longer online)

(Note: See harden as well.)

Definitions from Wiktionary (hardening) ▸ noun:  The process by which something hardens. ▸ noun:  Something which hardens. Similar: solidification, set, toughening, strain hardening, case hardening, thermohardening, precipitation hardening, work hardening, rigidization, steelification, more... Opposite: softening, weakening, relaxing, loosening Types: annealing, normalizing, tempering, case hardening, more... Phrases: strain hardening, work hardening, precipitation hardening, case hardening, surface hardening, more... Adjectives: case, isotropic, cyclic, rapid, kinematic, age, secondary, work, cold, gradual, solid Colors:     gunmetal,     charcoal,     iron,     graphite,     lead, more... ▸ Words similar to hardening ▸ Usage examples for hardening ▸ Idioms related to hardening ▸ Wikipedia articles (New!) ▸ Popular adjectives describing hardening ▸ Words that often appear near hardening ▸ Rhymes of hardening ▸ Invented words related to hardening