. . "A microorganism (from the Greek: \u03BC\u03B9\u03BA\u03C1\u03CC\u03C2, mikros, \"small\" and \u1F40\u03C1\u03B3\u03B1\u03BD\u03B9\u03C3\u03BC\u03CC\u03C2, organism\u00F3s, \"organism\") is a microscopic living organism, which may be single celled or multicellular. The study of microorganisms is called microbiology, a subject that began with the discovery of microorganisms in 1674 by Antonie van Leeuwenhoek, using a microscope of his own design.Microorganisms are very diverse and include all the bacteria and archaea and almost all the protozoa."@en . .