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 (prō′tə-zō′ən) also pro·to·zo·on (-ŏn′)
n. pl. pro·to·zo·ans or pro·to·zo·a (-zō′ə) also pro·to·zo·ons
Any of numerous chiefly single-celled eukaryotic organisms, most of which move about freely and ingest food, including the amoebas, ciliates, flagellates, and apicomplexans. Protozoans along with certain algae, oomycetes, and some other groups make up the protists.

[From New Latin Prōtozōa, former subkingdom name : proto- + -zōa, pl. of -zōon, -zoon.]

pro′to·zo′an, pro′to·zo′al, pro′to·zo′ic adj.


(Biology) another name for protozoan1


(ˌproʊ təˈzoʊ ən)

n., pl. -zo•ans, (esp. collectively) -zo•a (-ˈzoʊ ə)
adj. n.
1. any of various one-celled protist organisms that usu. obtain nourishment by ingesting food particles rather than by photosynthesis: classified as the superphylum Protozoa encompassing separate phyla according to means of movement, as by pseudopod, flagella, or cilia.
2. of, pertaining to, or characteristic of a protozoan.
[1860–65; < New Latin Protozo(a) (see proto-, -zoa) + -an1]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.protozoon - any of diverse minute acellular or unicellular organisms usually nonphotosyntheticprotozoon - any of diverse minute acellular or unicellular organisms usually nonphotosynthetic
protoctist - any of the unicellular protists
phylum Protozoa, Protozoa - in some classifications considered a superphylum or a subkingdom; comprises flagellates; ciliates; sporozoans; amoebas; foraminifers
sarcodine, sarcodinian - protozoa that move and capture food by forming pseudopods
rhizopod, rhizopodan - protozoa characterized by a pseudopod
arcella - an amoeba-like protozoan with a chitinous shell resembling an umbrella
difflugia - a protozoan with an ovoid shell of cemented sand grains
ciliate, ciliated protozoan, ciliophoran - a protozoan with a microscopic appendage extending from the surface of the cell
euglena - minute single-celled green freshwater organism having a single flagella; often classed as algae
flagellate, flagellate protozoan, flagellated protozoan, mastigophoran, mastigophore - a usually nonphotosynthetic free-living protozoan with whiplike appendages; some are pathogens of humans and other animals
plantlike flagellate - unicellular organisms having many characteristics of typical algae
sporozoan - parasitic spore-forming protozoan
cytostome - mouth of a protozoan


n. protozoo, organismo unicelular.


n (pl -zoa) protozoo, protozoario; [Nota: protozoan y protozoon se usan intercambiablemente para decir protozoo, pero para decir el plural, no se usa mucho protozoans, sino protozoa.]
References in periodicals archive ?
sup][1] In it, the authors question whether there is adequate evidence to consider this multiflagellated protozoon of significant importance in the context of the respiratory tract.
In 1880 a French physician, Charles-Louis-Alphonse Laveran (1845-1922), isolated the microorganism that caused malaria and, to everyone's astonishment, found it to be not a bacterium but a protozoon, a one-celled animal.
Although in 1998 and 1999 four books on virus induced cancer development were published, no book has been published to date describing the role of viruses, bacteria, parasite and protozoon induced tumorigenesis.