1. a rash of purple spots on the skin caused by internal bleeding from small blood vessels.
▪ any of a number of diseases characterized by such a rash:"psychogenic purpura"
Word Originlate 16th century (denoting a gastropod mollusc): from modern Latin, from Latin, ‘purple’, from Greek porphura. The sense ‘disease characterized by a purple rash’ dates from the mid 18th century.
