brux·ism 
(brŭksĭz′əm)
(brŭksĭz′əm)n.
The habitual, involuntary grinding or clenching of the teeth, usually during sleep.
[From New Latin brūxis, a gnashing, from Greek brūkein, to gnash.]
- percussively
- percussiveness
- percutaneous
- percutaneous coronary intervention
- percutaneously
- Percy
- Percy
- Percy Bysshe
- Percy Lavon
- (Percy) Wyndham
- per diem
- perdition
- perdu
- perdue
- perdurability
- perdurable
- perdurably
- perdure
- peregrinate
- peregrination
- peregrinator
- peregrine
- peregrine falcon
- Pereira
- Perelman