Caveat

[Latin, Let him beware.] A warning; admonition. A formal notice or warning given by an interested party to a court, judge, or ministerial officer in opposition to certain acts within his or her power and jurisdiction.

Originally, a caveat was a document that could be served on either a judge or a public official to give him or her notice that he or she should discontinue a certain proceeding until an opposing party was given an opportunity to be heard.

Used in the past by someone objecting to the appointment of an executor or administrator of an estate or to the granting of a patent for an invention, the term caveat is rarely used by modern attorneys.