Organisms adjectives are listed in this post. Each word below can often be found in front of the noun organisms in the same sentence. This reference page can help answer the question what are some adjectives commonly used for describing ORGANISMS.
active, adult, advanced, aerobic, allied, anaerobic, ancestral, ancient, animal, aquatic, associated, bacterial, beneficial, benthic, biological, causative, causing, cell, celled, cellular, certain, commensal, common, complete
complex, complicated, dead, developed, different, diploid, distinct, diverse, dwelling, earliest, elementary, encapsulated, enteric, entire, eukaryotic, extinct, fast, few, first, following, foreign, forming, fossil, freshwater
fungal, harmful, healthy, heterotrophic, higher, highest, human, important, independent, individual, infecting, infectious, infective, inferior, intracellular, invading, isolated, large, larger, like, little, live, living, low
lower, lowest, lowly, many, marine, micro, microbial, microscopic, minute, modern, modified, more, most, motile, multicelled, multicellular, multiple, natural, negative, new, nonhuman, nontarget, numerous, only
opportunistic, other, own, parasitic, particular, pathogenic, photosynthetic, physical, planktonic, political, positive, primitive, producing, prokaryotic, putrefactive, pyogenic, related, resistant, same, sensitive, separate, sessile, several, similar
simple, simpler, simplest, singlecelled, small, smaller, social, specific, such, susceptible, terrestrial, tiny, transgenic, unicellular, unrelated, unusual, various, viable, virulent, whole
Hope this word list had the adjective used with organisms you were looking for. Additional describing words / adjectives that describe / adjectives of various nouns can be found in the other pages on this website.