*amercement*

n. [ OF. amerciment. ] The infliction of a penalty at the discretion of the court; also, a mulct or penalty thus imposed. It differs from a fine, in that the latter is, or was originally, a fixed and certain sum prescribed by statute for an offense; but an amercement is arbitrary. Hence, the act or practice of affeering. [ See Affeer. ] Blackstone. [ 1913 Webster ]

☞ This word, in old books, is written amerciament. [ 1913 Webster ]

Amercement royal, a penalty imposed on an officer for a misdemeanor in his office. Jacobs. [ 1913 Webster ]