Single-celled organism
A single-celled organism was a lifeform which consisted of a single . This contrasted with a multicellular organism. Single-celled organisms were typically microorganisms.

In 2268, for lack of a better term, a space amoeba encountered by the crew of the  was described as a giant single-celled animal. ()

According to Doctor Beverly Crusher in 2364, cell division in single-celled lifeforms, at least organic ones, was preceded by a resting state. ()

In 2373, Captain Kathryn Janeway sarcastically stated it was flattering that Q chose her to be his mate over a single-celled organism after he mentioned he could have also chosen a Cyrillian microbe. ()

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Lifeform classifications
Biology