A lot vs. Alot: 9 Grammatical Pitfalls
pleomorphism ple·o·mor·phism (plē'ə-môr'fĭz'əm)
The occurrence of two or more structural forms during a life cycle, especially of certain plants.
the existence of irregular and variant forms in the same species or strain of microorganisms, a condition analogous to polymorphism in higher organisms. Pleomorphism is particularly prevalent in certain groups of bacteria and in yeasts, rickettsias, and mycoplasmas and greatly complicates the task of identifying and studying them.