1.(grind together)+ teeth(因疼痛、愤怒等)咬, 磨
2.+ food啃咬；咀嚼
3.to gnash your teeth
(be frustrated)咬牙切齿；非常愤怒；非常沮丧
If Blythe heard that piece, I bet he was gnashing his teeth.如果布莱思听说了那件事, 我肯定他会气得咬牙切齿。
If you couldn't attend the concert and are gnashing your teeth at having missed out, don't despair.如果你没能亲临音乐会并且正在为错过机会而沮丧的话, 不必绝望。