(a) The word "officer" shall be construed to refer to a commissioned officer;
(b) The word "soldier" shall be construed as including a noncommissioned officer, a private, or any other enlisted man;
(c) The word "company" shall be understood as including a troop or battery; and
(d) The word "battalion" shall be understood as including a squadron.
PERSONS SUBJECT TO MILITARY LAW.
Art. 2. The following persons are subject to these articles and shall be understood as included in the term "any person subject to military law" or "persons subject to military law" whenever used in these articles: Provided, That nothing contained in this act, except as specifically provided in article 2, subparagraph (c), shall be construed to apply to any person under the United States naval jurisdiction, unless otherwise specifically provided by law;
(a) All officers and soldiers belonging to the Regular Army of the United States; all volunteers, from the dates of their muster or acceptance into the military service of the United States; and all other persons lawfully called, drafted, or ordered into or to duty or for training in the said service, from the dates they are required by the terms of the call, draft, or order to obey the same.
(b) Cadets.
(c) Officers and soldiers of the Marine Corps when detached for service with the armies of the United States by order of the President: Provided, That an officer or soldier of the Marine Corps when so detached may be tried by military court-martial for an offense committed against the laws for the government of the naval service prior to his detachment, and for an offense committed against these articles he may be tried by a naval court-martial after such detachment ceases.
(d) All retainers to the camp and all persons accompanying or serving with the armies of the United States without the territorial jurisdiction of the United States, and in times of war all such retainers and persons accompanying or serving with the armies of the United States in the field, both within and without the territorial jurisdiction of the United States, though not otherwise subject to these articles.