We found 32 dictionaries that define the word grindstone:

General (25 matching dictionaries)

1. grindstone: Merriam-Webster
2. grindstone: Oxford Learner's Dictionaries
3. grindstone: American Heritage Dictionary of the English Language
4. grindstone: Collins English Dictionary
5. grindstone: Vocabulary.com
6. Grindstone, grindstone: Wordnik
7. grindstone: Cambridge Advanced Learner's Dictionary
8. grindstone: Wiktionary
9. grindstone: Webster's New World College Dictionary, 4th Ed.
10. grindstone: The Wordsmyth English Dictionary-Thesaurus
11. grindstone: Infoplease Dictionary
12. Grindstone, grindstone: Dictionary.com
13. grindstone: Cambridge Essential American English Dictionary
14. Grindstone (album), Grindstone (disambiguation), Grindstone (horse), Grindstone (time-tracking software), Grindstone (tool), Grindstone: Wikipedia, the Free Encyclopedia
15. Grindstone: Online Plain Text English Dictionary
16. grindstone: Webster's Revised Unabridged, 1913 Edition
17. grindstone: Rhymezone
18. Grindstone: AllWords.com Multi-Lingual Dictionary
19. grindstone: Webster's 1828 Dictionary
20. grindstone: FreeDictionary.org
21. grindstone: Mnemonic Dictionary
22. grindstone: TheFreeDictionary.com
23. grindstone: Longman Dictionary of Contemporary English

Art (1 matching dictionary)

24. Natural Magick (No longer online)

Computing (1 matching dictionary)

25. grindstone: Encyclopedia

Miscellaneous (2 matching dictionaries)

26. Brilliant Dream Dictionary (No longer online)
27. grindstone: Idioms

Science (1 matching dictionary)

28. Archaeology Wordsmith (No longer online)

Slang (1 matching dictionary)

29. grindstone: Urban Dictionary

Tech (1 matching dictionary)

30. AUTOMOTIVE TERMS (No longer online)

(Note: See grindstones as well.)

Definitions from Wiktionary ( ) ▸ noun:  An abrasive wheel for sharpening, polishing or grinding. ▸ noun:  Synonym of starry flounder Similar: grinding wheel, grinder, whetstone, sharpening stone, millstone, grindery, bench grinder, burr millstone, rubber, grinding frame, more... Opposite: whetstone, sharpener, honing stone Types: water, oil, electric, pneumatic, stone, more... Phrases: keep ones nose to the grindstone, keep one's nose to the grindstone, keep nose to the grindstone, keeping nose to the grindstone, keeps nose to the grindstone, more... Adjectives: old, large, small, revolving, great, common, upper, lower, big, wet, ordinary ▸ Words similar to grindstone ▸ Usage examples for grindstone ▸ Idioms related to grindstone ▸ Wikipedia articles (New!) ▸ Popular adjectives describing grindstone ▸ Words that often appear near grindstone ▸ Rhymes of grindstone ▸ Invented words related to grindstone