Protozoa

[proh-tuh-zoh-uh] /ˌproʊ təˈzoʊ ə/
noun
1.
a major grouping or superphylum of the kingdom Protista, comprising the protozoans.
Origin
1825-35; < Neo-Latin; see proto-, -zoa

protozoan

[proh-tuh-zoh-uh n] /ˌproʊ təˈzoʊ ən/
noun, plural protozoans (especially collectively) protozoa
[proh-tuh-zoh-uh] /ˌproʊ təˈzoʊ ə/ (Show IPA)
1.
any of a diverse group of eukaryotes, of the kingdom Protista, that are primarily unicellular, existing singly or aggregating into colonies, are usually nonphotosynthetic, and are often classified further into phyla according to their capacity for and means of motility, as by pseudopods, flagella, or cilia.
adjective
2.
of, pertaining to, or characteristic of a protozoan.
Origin
1860-65; Protozo(a) + -an

protozoon

[proh-tuh-zoh-on, -uh n] /ˌproʊ təˈzoʊ ɒn, -ən/
noun, plural protozoa
[proh-tuh-zoh-uh] /ˌproʊ təˈzoʊ ə/ (Show IPA)
1.
protozoan.
Origin
singular of Protozoa
Examples from the web for Protozoa
  • They are distinguished from Protozoa in that they are photosynthetic.
British Dictionary definitions for Protozoa

protozoan

/ˌprəʊtəˈzəʊən/
noun (pl) -zoa (-ˈzəʊə), -zoans
1.
Also called protozoon (ˌprəʊtəˈzəʊɒn), (pl) -zoa. any of various minute unicellular organisms formerly regarded as invertebrates of the phylum Protozoa but now usually classified in certain phyla of protoctists. Protozoans include flagellates, ciliates, sporozoans, amoebas, and foraminifers
adjective
2.
of or relating to protozoans
Word Origin
C19: via New Latin from Greek proto- + zoion animal
Word Origin and History for Protozoa
n.

1828, from Modern Latin Protozoa, coined 1818 by German zoologist Georg August Goldfuss (1782-1848) from Greek protos "first" (see proto-) + zoia, plural of zoion "animal" (see zoo). Originally including sponges and corals; current sense is from 1845. Related: Protozoon (aingular); Protozoan.

Protozoa in Medicine

protozoa pro·to·zo·a (prō'tə-zō'ə)
n.
Plural of protozoan.

protozoan pro·to·zo·an (prō'tə-zō'ən) or pro·to·zo·on (-ŏn')
n. pl. pro·to·zo·a (-zō'ə) or pro·to·zo·ans or pro·to·zo·a or pro·to·zo·ons
Any of a group of single-celled, usually microscopic, eukaryotic organisms, such as amoebas, ciliates, flagellates, and sporozoans.

pro'to·zo'an or pro'to·zo'al or pro'to·zo'ic adj.
Protozoa in Science
protozoan
  (prō'tə-zō'ən)   
Plural protozoans or protozoa
Any of a large group of one-celled organisms (called protists) that live in water or as parasites. Many protozoans move about by means of appendages known as cilia or flagella. Protozoans include the amoebas, flagellates, foraminiferans, and ciliates. Their traditional classification as the subkingdom Protozoa is still used for convenience, but it is now known that protozoans represent several evolutionarily distinct groups. See more at protist.
Protozoa in Culture
protozoa [(proh-tuh-zoh-uh)]

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.)

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