A microorganism, or microbe, [a] is an organism of microscopic size, which may exist in its single-celled form or as a colony of cells. The possible existence of unseen microbial life was suspected from …

Mar 28, 2024 · A microorganism, or microbe, is a tiny living organism that is invisible to the naked eye and can exist as single-celled entities or colonies of cells.

Dec 4, 2025 · Microbiology, the scientific study of microorganisms, a diverse group of generally minute simple life-forms, including bacteria, algae, and viruses. The field is concerned with the structure, …

Dec 5, 2016 · The meaning of MICROORGANISM is an organism (such as a bacterium or protozoan) of microscopic or ultramicroscopic size.

Add to word list biology a living thing which on its own is too small to be seen without a microscope (= device that makes small objects look larger) (Definition of microorganism from the Cambridge …

MICROORGANISM definition: any organism too small to be viewed by the unaided eye, as bacteria, protozoa, and some fungi and algae. See examples of microorganism used in a sentence.

Microorganisms, also known as microbes, are tiny living organisms that are invisible to the naked eye. They include a diverse group of microscopic life forms such as bacteria, archaea, fungi, protists, and …

A microorganism is a living entity that is too small to be seen unaided. This term encompasses bacteria, archaea, microscopic fungi, algae, and protozoa; viruses and prions, although not truly living, are …

A microorganism, or microbe, is an organism (form of life) that is microscopic (too small to be seen by the unaided human eye). Microorganisms can be bacteria, fungi, archaea, or protists, but not viruses …

Definition of microorganism noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.