The ongoing extinction of individual species due to environmental or ecological factors such as climate change, disease, loss of habitat, or competitive disadvantage in relation to other species. Background extinction occurs at a fairly steady rate over geological time and is the result of normal evolutionary processes, with only a limited number of species in an ecosystem being affected at any one time. Compare mass extinction.
- Background processing
noun (computing) the ability of a system to perform a low-priority task while, at the same time, dealing with a main application
- Background radiation
noun See cosmic background radiation background radiation back·ground radiation (bāk’ground’) n. Relatively constant low-level radiation from environmental sources such as building materials, cosmic rays, and ingested radionucleides in the body. Low-level radiation at the surface of the Earth that comes from cosmic rays and from small amounts of radioactive materials in rocks and the atmosphere.
having a back, backing, setting, or support (often used in combination): a low-backed sofa. (of fabric) having an extra set of threads in either the warp or the weft to provide added warmth. Compare double cloth. Photography. (of a film or plate) coated with a substance for absorbing light and thereby reducing halation. the rear […]
noun (Brit, informal) a ride on the back of someone’s bicycle