Protozoa

[proh-tuh-zoh-uh]

noun

1. a major grouping or superphylum of the kingdom Protista, comprising the protozoans.

protozoa

1. Single-celled animals, such as amoebas, that are the most primitive form of animal life. In modern biology, they are classified in the kingdom of Protoctista rather than in the animal kingdom. (See Linnean classification.)

Some protozoa are parasites and may be pathogenic, causing diseases such as malaria and dysentery.

Word History and Origins

Origin of protozoa¹

From New Latin, dating back to 1825–35; proto-, -zoa

Example Sentences

The host of life on ice includes bacteria, viruses, fungi, protozoa, even microscopic animals like nematodes, some dead and some alive in suspended animation.

From Salon

Organisms that can survive in this suspended, or anabiotic, state, Yarzábal explained, include not just extremophile bacteria but also viruses, fungi, protozoa and microscopic animals called nematodes.

From Salon

It seems miraculous that, over billions of years, our planetary circumstances enabled protozoa to evolve into people.

From New York Times

Bottom line: If you must have tropical milkweed, cut it down to the ground each fall before it goes to seed, to kill any overwintering protozoa and reduce its potential to spread to neighboring areas.

From Los Angeles Times

Food turns into compost through the hard work of small microorganisms like bacteria, fungi, and protozoa.

From National Geographic