small hard particles of sand, earth, stone, etc

any coarse sandstone that can be used as a grindstone or millstone

the texture or grain of stone

indomitable courage, toughness, or resolution

an arbitrary measure of the size of abrasive particles used in a grinding wheel or other abrasive process

to clench or grind together (two objects, esp the teeth)

to cover (a surface, such as icy roads) with grit