n. A. Middle English form of spur.n. In botany, a single cell which becomes free and is capable of developing directly into a new morphologically and physiologically independent individual.n. In zoology, the seed or germ of an organism, of minute size, and not of the morphological value of a cell, such as one of the microscopic bodies into which the substance of many protozoans is resolved in the process of reproduction by sporation; a sporule; a gemmule, as of a sponge.n. In biology, an organic body of extremely minute size, and not subject to ordinary classification; a sporozoid or zoöspore; a living germ, as a seed of certain diseases.n. Figuratively, a germ; a seed; a source of being.