grain

noun

• 1 [mass noun] wheat or any other cultivated cereal used as food.
• the seeds of wheat or other cultivated cereals.

• 2a single fruit or seed of a cereal:a few grains of corn
• a small hard particle of a substance such as salt or sand:a grain of salt
• the smallest possible quantity or amount of a quality:there wasn’t a grain of truth in what he said
• a discrete particle or crystal in a metal, igneous rock, etc., typically visible only when a surface is magnified.
• a piece of solid propellant for use in a rocket engine.

• 3 (abbreviation: gr.) the smallest unit of weight in the troy and avoirdupois systems, equal to 1/ 5760 of a pound troy and 1/ 7000 of a pound avoirdupois (approximately 0.0648 gram).

  [because originally the weight was equivalent to that of a grain of corn]

• 4 [mass noun] the longitudinal arrangement or pattern of fibres in wood, paper, etc.:he scored along the grain of the table with the knife
• the texture of wood, stone, etc., as determined by the arrangement and size of constituent particles:the lighter, finer grain of the wood is attractive
• the rough or wrinkled outer surface of leather, or of a similar artificial material.
• Mining lamination or planes of cleavage in materials such as stone and coal.
• Photography a grainy appearance of a photograph or negative, which is in proportion to the size of the emulsion particles composing it.

• 5 archaic a person’s character or natural tendency.

• 6 [mass noun] historical kermes or cochineal, or dye made from either of these.

verb

• 1give a rough surface or texture to:her fingers were grained with chalk dust
• [no object] form into grains: if the sugar does grain up, add more water

• 2 (usually as noun graining) paint (especially furniture or interior surfaces) in imitation of the grain of wood or marble.

• 3remove hair from (a hide).

• 4North American feed (a horse) on grain.