Definition of floor. 1  1 : the level base of a room. 2  2a : the lower inside surface of a hollow structure (such as a cave or bodily part)b : a ground surface the ocean floor. 3  3a : a structure dividing a building into stories; also : storyb : the occupants of such a floor. 4  4 : the surface of a structure on which one travels the floor of a bridge.
The Black Death was an epidemic outbreak of bubonic plague in Europe around 1348 that killed between one-third and two-thirds of the population in less than five years. The epidemic spanned from China to England to North Africa, transmitted along the Silk Road and other trade routes. Worldwide, the plague may have killed one-quarter of all people. Repeated outbreaks continued in Europe into the 18th century. Some historians believe the drastic reduction in population hurried the end of feudalism by raising the value of labor and the power of workers, as seen in incidents like the 1381 Peasants Revolt in England.
brain death. Etymology: AS, bragen + death. an irreversible form of unconsciousness characterized by a complete loss of brain function while the heart continues to beat. The legal definition of this condition varies from state to state. The usual clinical criteria for brain death include the absence of reflex activity, movements, and spontaneous respiration requiring mechanical ventilation or life support to continue any cardiac function. The pupils are dilated and fixed.