τρίζω trízō

Meaning

to creak (squeak), i.e. (by analogy) to grate the teeth (in frenzy)

In the King James Version: gnash

Derivation: apparently a primary verb;

Where it is used

• Mark 9:18 Whenever it seizes him, it throws him to the ground. He foams at the mouth, gnashes his teeth, and becomes rigid. I asked Your disciples to drive it out, but they were unable.”