While there are differing opinions on exactly who qualifies as a U.S. Army veteran, the general definition is any soldier who, at one time, served in the armed forces. There is no legal definition of the term, however, despite over two centuries of laws passed by the U.S. Congress.
Whether or not someone is considered a military veteran often depends entirely upon the benefit or program for which the person is applying. It is the habit of Congress to specify the eligibility for a particular benefit as the law providing that benefit is approved. For example, in order to qualify for a VA home loan, a veteran must have been discharged from service for other than dishonorable reasons.