n. The act of closing the teeth and showing them, or of withdrawing the lips and showing the teeth; a hard, forced, or sneering smile. I.Watts. [ 1913 Webster ]

He showed twenty teeth at a grin. Addison. [ 1913 Webster ]

v. t. To express by grinning. [ 1913 Webster ]

Grinned horrible a ghastly smile. Milton.

v. i. [ imp. & p. p. Grinned p. pr. & vb. n. Grinning. ] [ OE. grinnen, grennen, AS. grennian, Sw. grina; akin to D. grijnen, G. greinen, OHG. grinan, Dan. grine. √35. Cf. Groan. ] 1. To show the teeth, as a dog; to snarl. [ 1913 Webster ]

2. To set the teeth together and open the lips, or to open the mouth and withdraw the lips from the teeth, so as to show them, as in laughter, scorn, or pain. [ 1913 Webster ]

The pangs of death do make him grin. Shak. [ 1913 Webster ]

n. [ AS. grin. ] A snare; a gin. [ Obs. ] [ 1913 Webster ]

Like a bird that hasteth to his grin. Remedy of Love. [ 1913 Webster ]

v. t. [ imp. & p. p. Ground p. pr. & vb. n. Grinding. ] [ AS. grindan; perh. akin to L. frendere to gnash, grind. Cf. Grist. ] 1. To reduce to powder by friction, as in a mill, or with the teeth; to crush into small fragments; to produce as by the action of millstones. [ 1913 Webster ]

Take the millstones, and grind meal. Is. xivii. 2. [ 1913 Webster ]

2. To wear down, polish, or sharpen, by friction; to make smooth, sharp, or pointed; to whet, as a knife or drill; to rub against one another, as teeth, etc. [ 1913 Webster ]

3. To oppress by severe exactions; to harass. [ 1913 Webster ]

To grind the subject or defraud the prince. Dryden. [ 1913 Webster ]

4. To study hard for examination; -- commonly used with away; as, to grind away at one's studies. [ College Slang ] [ 1913 Webster ]

v. i. 1. To perform the operation of grinding something; to turn the millstones. [ 1913 Webster ]

Send thee
Into the common prison, there to grind. Milton. [ 1913 Webster ]

2. To become ground or pulverized by friction; as, this corn grinds well. [ 1913 Webster ]

3. To become polished or sharpened by friction; as, glass grinds smooth; steel grinds to a sharp edge. [ 1913 Webster ]

4. To move with much difficulty or friction; to grate. [ 1913 Webster ]

5. To perform hard and distasteful service; to drudge; to study hard, as for an examination. Farrar. [ 1913 Webster ]

n. 1. The act of reducing to powder, or of sharpening, by friction. [ 1913 Webster ]

2. Any severe continuous work or occupation; esp., hard and uninteresting study. [ Colloq. ] T. Hughes. [ 1913 Webster ]

3. A student that studies hard; a dig; a wonk. [ College Slang ] [ 1913 Webster +PJC ]

obs. p. p. of Grind. Ground. Sir W. Scott. [ 1913 Webster ]

‖n. [ NL. Named after D. H. Grindel, a Russian. ] (Med.) The dried stems and leaves of tarweed (Grindelia), used as a remedy in asthma and bronchitis. [ 1913 Webster ]

n. 1. One who, or that which, grinds. [ 1913 Webster ]

2. One of the double teeth, used to grind or masticate the food; a molar. [ 1913 Webster ]

3. (Zool.) The restless flycatcher (Seisura inquieta) of Australia; -- called also restless thrush and volatile thrush. It makes a noise like a scissors grinder, to which the name alludes.

4. A submarine sandwich. [ local, U.S. ]
Syn. -- submarine, hoagie. [ PJC ]

Grinder's asthma,
Grinder's phthisis, or
Grinder's rot (Med.), a lung disease produced by the mechanical irritation of the particles of steel and stone given off in the operation of grinding. [ 1913 Webster ]