n a syndrome that occurs in many women from 2 to 14 days before the onset of menstruation n an examination and dissection of a dead body to determine cause of death or the changes produced by disease n a soft silvery metallic element of the rare earth group having no stable isotope; was discovered in radioactive form as a fission product of uranium n the person who holds the position of head of the government in the United Kingdom n modulation of the phase of the carrier wave