What is Ministerial Act?

Legal Definition
A ministerial act is a government action "performed according to legal authority, established procedures or instructions from a superior, without exercising any individual judgment." It can be any act a functionary or bureaucrat performs in a prescribed manner, without exercising any individual judgment or discretion. Under law, this would be classified under the rubric of public policy.
-- Wikipedia
Legal Definition
A ministerial act may be defined to be one which a person performs in a given state of facts, in a prescribed manner, in obedience to the mandate of legal authority, without regard to or the exercise of his own judgment, upon the propriety of the act being done. Acts done out of court in bringing parties into court are, as a general proposition, ministerial acts. Pennington v. Streight, 54 Ind. 376 ; Bair v. Struck, 29 Mont. 45, 74 Pac. 69, 63 I). R. A. 481; State v. Nash, 66 Ohio St. 612, 64 N. E. 558: Grider v. Tally, 77 Ala. 424, 54 Am. Rep. 65.
-- Black's Law Dictionary
Legal Definition
One which a person performs under a given state of facts, in a prescribed manner, in obedience to the mandate of legal authority, and without regard to or exercise of his own judgment upon the propriety of the act being done. See 25 Am. St. Rep. 342, note.
-- Ballentine's Law Dictionary