Noah Webster's New International Dictionary of the English Language
1. (n.) A prayer; a supplication; an imploration; an entreaty; especially, a request of a solemn or formal kind; a prayer to the Supreme Being, or to a person of superior power, rank, or authority; also, a single clause in such a prayer.
2. (n.) A formal written request addressed to an official person, or to an organized body, having power to grant it; specifically (Law), a supplication to government, in either of its branches, for the granting of a particular grace or right; -- in distinction from a memorial, which calls certain facts to mind; also, the written document.
3. (v. t.) To make a prayer or request to; to ask from; to solicit; to entreat; especially, to make a formal written supplication, or application to, as to any branch of the government; as, to petition the court; to petition the governor.
4. (v. i.) To make a petition or solicitation.