(Encyclopedia) gas, in physics, one of the three commonly recognized states of matter, the other two being solid and liquid. A substance in the gaseous state has neither definite shape nor definite…
(Encyclopedia) Erdös, PaulErdös, Paulĕrˈdös [key], 1913–96, Hungarian mathematician, b. Budapest. A child prodigy, he was mostly home-schooled by his parents—both teachers of mathematics—until he…
(Encyclopedia) diarrheadiarrheadīərēˈə [key], frequent discharge of watery feces from the intestines, sometimes containing blood and mucus. It can be caused by excessive indulgence in alcohol or…
(Encyclopedia) echo sounder, an older instrumentation system for indirectly determining ocean floor depth. Echo sounding is based on the principle that water is an excellent medium for the…
(Encyclopedia) defoliant, any one of several chemical compounds that, when applied to plants, can alter their metabolism, causing the leaves to drop off. In agriculture defoliants are used to…
(Encyclopedia) draft, in banking, order by one party to another party to pay a stated sum to the person or firm in whose favor the draft is made. It is similar in form to the ordinary bank check.…
(Encyclopedia) Domesday BookDomesday Bookd&oomacr;mzˈdā [key], record of a general census of England made (1085–86) by order of William I (William the Conqueror). The survey ascertained the…
(Encyclopedia) congenital heart disease, any defect in the heart present at birth. There is evidence that some congenital heart defects are inherited, but the cause of most cases is unknown. One…
(Encyclopedia) decompression sickness, physiological disorder caused by a rapid decrease in atmospheric pressure, resulting in the release of nitrogen bubbles into the body tissues. It is also known…
