The kiss of death (Italian: Il bacio della morte) is the sign given by a mafioso boss or caporegime that signifies that a member of the crime family has been marked for death, usually as a result of some perceived betrayal.
[1] It is unclear how much is based on fact and how much on the imagination of authors, but it remains a cultural meme[2][3] and appears in literature and films.
The "kiss" has also been used as a terror tactic to aid in extortion or debt collection by reducing victims to a state of panic where they will commit to anything to save their lives.
[1] The exact origin is unknown, but an Italian source identifies the bacio della morte as the kiss given to the assassin delegated to "execute" a death sentence, as if to seal the solemn judgment and to wish success on the assignment.
Some believe it refers to the kiss of Judas which was given to Jesus to betray him to the soldiers seeking him out.