The word grain has several meanings, most being descriptive of a small piece or particle. A particle is Look up Particle in Wiktionary, the free dictionary In particle physics, a basic unit of matter or energy. ...

Particle-related

The primary definition is the agricultural one, with the others derived from it.

• In agriculture, a grain is the seed of a grass, a simple dry fruit technically called a caryopsis. Such crops are often called cereals. Grain can also refer to other types of small seeds, though this is technically less correct.
• In units of measurement, the grain is a unit of mass, originally based on the weight of one grain of barley. One gram of metric weight equals 15.4323584 grains. It was used in the past for older drugs such as aspirin, for bullets, and for precious metals.
• In geology, a grain is a single particle of rock or other material, such as sand or salt; see grain size.
• In materials science (especially metallurgy), a grain is a single crystal inside solid-state matter, also referred to as crystallite — related to the obsolete term "corn" as in corned beef.
• In photography, the fineness of image resolution for photographic film (i.e., graininess of a picture), originally related to the (crystallographic) grain size of silver iodide.

A seed is the ripened ovule of gymnosperm or angiosperm plants. ... Subfamilies There are 7 subfamilies: Subfamily Arundinoideae Subfamily Bambusoideae Subfamily Centothecoideae Subfamily Chloridoideae Subfamily Panicoideae Subfamily Pooideae Subfamily Stipoideae The true grasses are monocotyledonous plants (Class Liliopsida) in the Family Poaceae, formerly also known as Gramineae. ... Fruit stall in Barcelona, Spain. ... In botany, a caryopsis is a type of simple dry fruit — one that is moncarpelate (formed from a single carpel) and indehiscent (not opening at maturity) and resembles an achene, except that in a caryopsis the pericarp is fused with the thin seed coat. ... Cereal crops are mostly grasses cultivated for their edible seeds (actually a fruit called a caryopsis). ... Measurement is the determination of the size or magnitude of something. ... A grain is a unit of mass equal to 0. ... Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... Binomial name Hordeum vulgare L. Barley (Hordeum vulgare) is a major food and animal feed crop, a member of the grass family Poaceae. ... The gram is the basic diction unit of the metric weight system. ... Many drugs are provided in tablet form. ... A very old bottle of Aspirin Aspirin or acetylsalicylic acid is a drug in the family of salicylates, often used as an analgesic (against minor pains and aches), antipyretic (against fever), and anti-inflammatory. ... 0. ... A precious metal is a rare metallic element of high, durable economic value. ... Geology (from Greek γη- (ge-, the earth) and λογος (logos, word, reason)) is the science and study of the Earth, its composition, structure, physical properties, history, and the processes that shape it. ... Patterns in the sand Sand is an example of a class of materials called granular matter. ... In chemistry, salt is a term used for ionic compounds composed of positively charged cations and negatively charged anions, so that the product is neutral and without a net charge. ... This article deals with grain size in the context of geology, see crystallite for grain size in materials science. ... The Materials Science Tetrahedron Materials science is a multidisciplinary field focusing on functional solids, whether the function served is structural, electronic, thermal, chemical, magnetic, optical, or some combination of these. ... Metallurgy is a domain of materials science and of materials engineering that studies the physical and chemical behavior of metallic elements and their mixtures, which are called alloys. ... A crystallite is a domain of solid-state matter that has the same structure as a single crystal. ... Corned beef is beef that is first pickled in brine and then cooked by boiling. ... Lens and mounting of a large format camera Photography is the process of making pictures by means of the action of light. ... The image resolution is a term that says something about how much image detail an image can hold. ... Undeveloped Arista black and white film, ISO 125. ... Silver iodide (chemical symbol: AgI) is a chemical compound used in photography and cloud seeding. ...

Others

• In wood, grain describes the alignment and texture of the wood fibres. This is often important in its effect on woodworking techniques (e.g. going against the grain).
• In golf, the direction in which individual blades of grass lie, usually in reference to a putting green.
• In rocket science, grain refers to the solid propellant of a rocket (either solid fuelled or hybrid), more or less a hollow cylinder, sometimes textured inside, and possibly very large.
• In computer science Grain refers to the size of code executed by a thread or process before it is interrupted in a multiprocess system. Thus we have fine-grained and coarse grained parallelism.
• Grain may refer to the place Isle of Grain in Kent, England, on which lies the village of Grain, Kent.
• Grain is one of the stocks in the game Stock Ticker.
• In music, see granular synthesis.