- Also ameba. A single-celled (protozoan) organism that constantly changes shape. The word “ameba” is from the Greek “amoibe” meaning “change.” Ameba can infect the bowels to cause diarrhea and the liver to cause abscess formation.
* * *A genus of naked, lobose, pseudopod-forming protozoa of the class Sarcodina (or Rhizopoda), that are abundant soil-dwellers, especially in rich organic debris, and are also commonly found as parasites. The typical amebic parasites of humans are now placed in the genera Entamoeba, Endolimax, and Iodamoeba. SEE ALSO: Naegleria. [Mod. L. fr. G. amoibe change]- A. buccalis former name for Entamoeba gingivalis.- A. coli old, incorrect name Entamoeba coli.- A. dentalis former name for Entamoeba gingivalis.- A. dysenteriae old, incorrect name for Entamoeba histolytica.- A. histolytica old, incorrect name for Entamoeba histolytica.- A. proteus an abundant, nonparasitic species, remarkable for the number and varied shapes of its pseudopodia.
* * *Amoe·ba ə-'mē-bə n a large genus of naked rhizopod protozoans that have lobed and never anastomosing pseudopodia and are widely distributed in fresh and salt water and moist terrestrial environments
* * *n. (pl. amoebae)any protozoan of jelly-like consistency and irregular and constantly changing shape. Found in water, soil and other damp environments, they move and feed by means of flowing extensions of the body (see pseudopodium). Some amoebae cause disease in humans (see Acanthamoeba, Entamoeba).• amoebic adj.
* * *Amoe·ba (ə-meґbə) [L., from Gr. amoibē change] a genus of ramicristate amebae, protozoa now classified in the order Euamoebida; species have a vesicular nucleus, usually one contractile vacuole, and lobopodia, and are usually free living. Numerous species once included in this genus have been assigned to other genera.
Medical dictionary. 2011.