(Greek, δια through, and βάρος to go), an immoderate flow of urine. There are two varieties of this disorder; one a mere superabundance of the ordinary discharge; the other, termed diabetes mellitus, in which the urine becomes highly charged with saccharine matter, and which usually, if not always, terminates fatally.

DIACOUSTIC CURVE, a species of the caustic curves formed by refraction.