[mee-dee-uhm] 
noun, plural -di⋅a [-dee-uh] for 1–9, 11, -di⋅ums for 1–11, 14, adjective | 1. | a middle state or condition; mean. |
| 2. | something intermediate in nature or degree. |
| 3. | an intervening substance, as air, through which a force acts or an effect is produced. |
| 4. | the element that is the natural habitat of an organism. |
| 5. | surrounding objects, conditions, or influences; environment. |
| 6. | an intervening agency, means, or instrument by which something is conveyed or accomplished: Words are a medium of expression. |
| 7. | one of the means or channels of general communication, information, or entertainment in society, as newspapers, radio, or television. |
| 8. | Biology. the substance in which specimens are displayed or preserved. |
| 9. | Also called culture medium. Bacteriology. a liquid or solidified nutrient material suitable for the cultivation of microorganisms. |
| 10. | a person through whom the spirits of the dead are alleged to be able to contact the living. |
| 11. | Fine Arts.
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| 12. | a size of printing paper, 18 1/2 × 23 1/2 in. (47 × 60 cm) in England, 18 × 23 to 19 × 25 in. (46 × 58 to 48 × 64 cm) in America. |
| 13. | Chiefly British. a size of drawing or writing paper, 17 1/2 × 22 in. (44 × 56 cm). |
| 14. | Also called medium strip. Midland U.S. median strip. |
| 15. | in medium, Movies, Television. with the principal actors in the middle distance: The scene was shot in medium. |
| 16. | about halfway between extremes, as of degree, amount, quality, position, or size: Cook over medium heat. He is of medium height. |
| culture medium n. A liquid or gelatinous substance containing nutrients in which microorganisms or tissues are cultivated for scientific purposes. |
culture medium n.
A liquid or gelatinous substance containing nutrients in which microorganisms or tissues are cultivated for scientific purposes.
medium me·di·um (mē'dē-əm)
n. pl. me·di·ums or me·di·a (-dē-ə)
Something, such as an intermediate course of action, that occupies a position or represents a condition midway between extremes.
An intervening substance through which something else is transmitted or carried on.
An agency by which something is accomplished, conveyed, or transferred.
The substance, often nutritive, in which a specific organism lives and thrives.
A culture medium.
A filtering substance, such as filter paper.
| medium (mē'dē-əm) Pronunciation Key
Plural media
|
culture medium
solution freed of all microorganisms by sterilization (usually in an autoclave, where it undergoes heating under pressure for a specific time) and containing the substances required for the growth of microorganisms such as bacteria, protozoans, algae, and fungi. The medium may be solidified by the addition of agar. Some media consist of complex ingredients such as extracts of plant or animal tissue (e.g., peptone, meat extract, yeast extract); others contain exact quantities of known inorganic salts and one or more organic compounds (synthetic or chemically defined media). Various types of living cells, or tissue cultures, also may be used as media. Many special-purpose media are used in microbiology. These include enriched media, which contain nutrients in addition to those found in the usual growth medium, and selective media, which contain substances that prevent the growth of certain organisms but not others
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