What is Articles Of Impeachment?

Legal Definition
The articles of impeachment are the set of charges drafted against a public official to initiate the impeachment process. The articles of impeachment do not result in the removal of the official, but instead require the enacting body to take further action, such as bringing the articles to a vote before the full body.

In the United States, the articles of impeachment are drafted by the House of Representatives for cases involving federal officials. Once drafted, a supermajority of the United States Senate is required to convict based on the articles.
-- Wikipedia
Legal Definition
An instrument which, in cases of impeachment, (q. v.) is used, and performs the same office which an indictment does, in a common criminal case, is known by this name. These articles do not usually pursue the strict form and accuracy of an indictment., Wood. Lect. 40, p. 605; Foster, 389, 390; Com. Dig. Parliament, L 21. They are sometimes quite general in the form of the allegations, but always contain, or ought to contain, so much certainty, as to enable the party to put himself on the proper defence, and in case of an acquittal, to avail himself of it, as a bar to another impeachment. Additional articles may, perhaps, be exhibited at any stage of the prosecution. Story on the 806; Rawle on the Const. 216.

2. The answer to articles of impeachment is exempted from observing great strictness of form; and it may contain arguments as well as facts. It is usual to give a full and particular answer to each article of the accusation. Story, 808.
-- Bouviers Law Dictionary
Legal Definition
The formal written allegation of the causes for an impeachment, answering the same purpose as an indictment in an ordinary criminal proceeding.
-- Black's Law Dictionary
Legal Definition
The formal written charge against the defendant in an impeachment proceeding.
-- Ballentine's Law Dictionary