In biology, the adjective unicellular describes an organism that has only one single cell, like most kinds of bacteria.

You're most likely to see the word unicellular in a biology textbook, where it is used to talk about microscopic, single-celled organisms. Many types of fungi are unicellular, as well as amoebas, bacteria, and other tiny creatures and plants. The word unicellular combines the Latin prefix meaning "one," uni, and the word cellular, which has the root word cella, "small room."

Definitions of unicellular

adj having or consisting of a single cell

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