from The American Heritage® Dictionary of the English Language, 4th Edition
- transitive v. To grind or strike (the teeth, for example) together.
- transitive v. To bite (something) by grinding the teeth.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- v. To grind one's teeth in pain or in anger.
- v. To run away
from the GNU version of the Collaborative International Dictionary of English
- transitive v. To strike together, as in anger or pain.
- intransitive v. To grind or strike the teeth together.
from The Century Dictionary and Cyclopedia
- To snap, grate, or grind (the teeth) together, as in anger or pain.
- To snap or grate the teeth together, as in rage or pain.
- n. A snap; a sudden bite.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- v. grind together, of teeth
Alteration of Middle English gnasten, gnaisten, possibly of Scandinavian origin; akin to Old Norse gnastan, a gnashing.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Middle English gnasten. Origin unknown; the word is probably either Germanic or onomatopoeic. Compare Old Norse gnastan, German knirschen, German Low German gnirschen, gnörschen. (Wiktionary)