gritted

from The Collaborative International Dictionary of English v.0.48

Grit \Grit\, v. t. [imp. & p. p. {Gritted}; p. pr. & vb. n.
   {Gritting}.]
   To grind; to rub harshly together; to grate; as, to grit the
   teeth. [Collog.]
   [1913 Webster]