Ameba: A single-celled, protozoan organism that constantly changes shape. Amebae can infect the bowels, causing diarrhea. They can also infect the liver, causing abscesses to form.
Amebiasis: The state of being infected with amebae, especially with the ameba Entamoeba histolytica.
- Amebic colitis
Amebic colitis: Amebic dysentery with ulcers in the colon from infection with the ameba Entamoeba histolytica. This single-celled parasite is transmitted to humans via contaminated water and food.
- Amebic dysentery
Amebic dysentery: Inflammation of the intestine due to infection with the ameba Entamoeba histolytica. Amebic dysentery can be accompanied by amebic infection of the liver and other organs.
Amelanotic: Without melanin. A skin lesion that is amelanotic lacks the pigment melanin and, therefore, is essentially colorless.
- Amelanotic melanoma
Amelanotic melanoma: A colorless melanoma that is detectable only on close examination of the skin.