The crossword solution for the term VICIOUS ON STAGE is SID, which is an acronym for 'Sudden Infant Death Syndrome'. SIDS is a condition in which an infant dies suddenly and unexpectedly, usually during sleep. It is the leading cause of death among infants between one month and one year of age. The term VICIOUS ON STAGE is often used to describe the sudden and unexpected death of an infant due to SIDS.