spore Meaning, Definition & Usage

noun a small usually single-celled asexual reproductive body produced by many nonflowering plants and fungi and some bacteria and protozoans and that are capable of developing into a new individual without sexual fusion
- a sexual spore is formed after the fusion of gametes

Gr. a sowing, seed, from to sow. Cf. Sperm.

(Bot.) (a) One of the minute grains in flowerless plants, which are analogous to seeds, as serving to reproduce the species. ✍ Spores are produced differently in the different classes of cryptogamous plants, and as regards their nature are often so unlike that they have only their minuteness in common. The peculiar spores of diatoms (called auxospores) increase in size, and at length acquire a siliceous coating, thus becoming new diatoms of full size. Compare Macrospore, Microspore, Oöspore, Restingspore, Sphærospore, Swarmspore, Tetraspore, Zoöspore, and Zygospore. (b) An embryo sac or embryonal vesicle in the ovules of flowering plants.
(Biol.) (a) A minute grain or germ; a small, round or ovoid body, formed in certain organisms, and by germination giving rise to a new organism; as, the reproductive spores of bacteria, etc. (b) One of the parts formed by fission in certain Protozoa. See Spore formation, belw.