Retene

A hydrocarbon occurring in the highest fractions of coal-tar and also a derivative of phenanthrene. It occurs in the tar of highly resinous pines and in some mineral resins. It is very soluble in alcohol and benzene, and crystallizes in leaflets with a mother-of-pearl luster; it melts at 980 C, and boils at about 3900 C. Retention (re-ten' 'shim). The holding back or stoppage of any of the natural discharges of the body, as the feces, lochia, urine, menstrual flow, etc. a formed by a secretion, the natural outlet being closed. R., Hystero-cystic, retention of urine caused by pre ure from a gravid uterus. R. of Milk. Same as Galactoschesis, q. v. R. of Menses: 1. Retention of menstrual blood due to mechanical interference with its outward flow. 2. Postponement of menstrua tion after the proper age for its establishment. R. of Placenta, failure of expulsion of a placenta as a result of improper or deficient uterine contractions. R. of Urine, inability to empty the bladder voluntarily.