noun The harvested seeds of various grass food crops, especially wheat, maize, rye, barley, and rice.
We stored a thousand tons of grain for the winter.
noun Similar seeds from any food crop, e.g., buckwheat, amaranth, quinoa.
noun A single seed of a food crop, especially a cereal grass crop.
a grain of wheat
noun The crops from which grain is harvested.
The fields were planted with grain.
noun A linear texture of a material or surface.
Cut along the grain of the wood.
noun A single particle of a substance.
a grain of sand
noun Any of various small units of mass originally notionally based on grain's weight, variously standardized at different places and times, including: The English grain of ⁄5760 troy pound or ⁄7000 pound avoirdupois, now exactly 64.79891 mg.
noun The English grain of ⁄5760 troy pound or ⁄7000 pound avoirdupois, now exactly 64.79891 mg.