n. 1. An individual, group, structure, or other entity regarded as an elementary structural or functional constituent of a whole. 2. A group regarded as a distinct entity within a larger group. 3. a. A mechanical part or module. b. An entire apparatus or the equipment that performs a specific function. 4. A precisely specified quantity in terms of which the magnitudes of other quantities of the same kind can be stated. 5. Medicine The quantity of a vaccine, serum, drug, or other agent necessary to produce a specific effect. 6. a. A fixed amount of scholastic study used as a basis for calculating academic credits, usually measured in hours of classroom instruction or laboratory work. b. A section of an academic course focusing on a selected theme: a unit on Native Americans. 7. The number immediately to the left of the decimal point in the Arabic numeral system. 8. Mathematics a. The lowest positive whole number; one. b. An element of a ring with a multiplicative inverse. [Back-formation from UNITY.] |
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