*blackmail*

n. [ Black + mail a piece of money. ] 1. A certain rate of money, corn, cattle, or other thing, anciently paid, in the north of England and south of Scotland, to certain men who were allied to robbers, or moss troopers, to be by them protected from pillage. Sir W. Scott. [ 1913 Webster ]

2. Payment of money exacted by means of intimidation; also, extortion of money from a person by threats of public accusation, exposure, or censure. [ 1913 Webster ]

3. (Eng. Law) Black rent, or rent paid in corn, flesh, or the lowest coin, a opposed to “white rent”, which paid in silver. [ 1913 Webster ]

To levy blackmail, to extort money by threats, as of injury to one's reputation. [ 1913 Webster ]