\A*merce"ment\, 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 statue for an offense; but an
amercement is arbitrary. Hence, the act or practice of
affeering. [See {Affeer}.] --Blackstone.
Note: This word, in old books, is written amerciament.
{Amercement royal}, a penalty imposed on an officer for a
   misdemeanor in his office. --Jacobs.