We found 25 dictionaries that define the word seriousness:

General (19 matching dictionaries)

1. seriousness: Longman Dictionary of Contemporary English
2. seriousness: Merriam-Webster
3. seriousness: Oxford Learner's Dictionaries
4. seriousness: Collins English Dictionary
5. seriousness: Vocabulary.com
6. Seriousness, seriousness: Wordnik
7. seriousness: Cambridge Advanced Learner's Dictionary
8. seriousness: Wiktionary
9. seriousness: Dictionary.com
10. seriousness: Cambridge Essential American English Dictionary
11. Seriousness: Wikipedia, the Free Encyclopedia
12. seriousness: Rhymezone
13. seriousness: Webster's 1828 Dictionary
14. seriousness: Stammtisch Beau Fleuve Acronyms
15. seriousness: FreeDictionary.org
16. seriousness: Mnemonic Dictionary
17. seriousness: TheFreeDictionary.com

Business (1 matching dictionary)

18. seriousness: Legal dictionary

Medicine (2 matching dictionaries)

19. seriousness: Merriam-Webster Medical Dictionary
20. seriousness: Medical dictionary

Miscellaneous (2 matching dictionaries)

21. Encyclopedia of Graphic Symbols (No longer online)
22. seriousness: Idioms

Slang (1 matching dictionary)

23. seriousness: Urban Dictionary

(Note: See serious as well.)

Definitions from Wiktionary (seriousness) ▸ noun:  The state or quality of being serious. Similar: earnestness, distressfulness, sincerity, serious-mindedness, seriosity, semiseriousness, solemnness, unseriousness, serosity, self-seriousness, more... Opposite: frivolity, levity Types: solemn, grave, earnest, humorous, jesting, playful, frivolous, more... Phrases: in all seriousness, lack of seriousness, lacking seriousness, seriousness escalation, the seriousness of a situation, more... Adjectives: high, great, utmost, moral, mock, deep, deadly, much, full, intense, relative ▸ Words similar to seriousness ▸ Usage examples for seriousness ▸ Idioms related to seriousness ▸ Wikipedia articles (New!) ▸ Popular adjectives describing seriousness ▸ Words that often appear near seriousness ▸ Rhymes of seriousness ▸ Invented words related to seriousness