Spore :  (noun)

1: a small usually single-celled reproductive body produced by many plants and some protozoans and that develops into a new individual; "a sexual spore is formed after the fusion of gametes"

adenovirus, aerobe, aerobic bacteria, amoeba, anaerobe, anaerobic bacteria, bacillus, bacteria, bacterium, basidium, bug, coccus, cystocarp, disease-producing microorganism, echovirus, enterovirus, filterable virus, fungus, germ, gram-negative bacteria, gram-positive bacteria, macrospore, megaspore, microbe, microorganism, microsporangium, microspore, mold, nonfilterable virus, pathogen, picornavirus, planospore, protozoa, protozoon, reovirus, rhinovirus, rickettsia, sorus, spirillum, spirochete, sporangium, sporocarp, sporocyst, sporocyte, sporophore, sporophyte, sporule, staphylococcus, streptococcus, swarm spore, trypanosome, vibrio, virus, zoospore, zygospore,