Substance consisting of particles not exceeding 1 ?m dispersed in a fluid

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Very fine solid particles that will not settle out of a solution or medium. Smoke is an example of a colloid, being solid particles suspended in a gas. Colloids are the intermediate stage between a truly dissolved particle and a suspended solid, which will settle out of solution.

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A mixture in which one substance is divided into minute particles (called colloidal particles) and dispersed throughout a second substance. The mixture is also called a colloidal system, colloidal solution, or colloidal dispersion. Colloid science is the study of systems involving small particles of one substance suspended in another. Suspensions in liquids form the basis of a wide variety of systems of scientific and technological importance, including paints, ceramics, cosmetics, agricultural sprays, detergents, soils, biological cells, and many food preparations.

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Material with finely distributed solid particles that forms one of the key foundations of chemical nanotechnology.

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Very small particles (within the 1nm-to-1000nm range) that remain dispersed in a liquid for a long time. Their small size prevents them from being filtered easily or settled rapidly

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