The rank and file are the individual members of a political organization or labor union, exclusive of its leadership. The phrase originated in the military, denoting the horizontal "ranks" and vertical "files" of individual foot-soldiers, exclusive of the officers and is still sometimes used to refer to the bulk of lower-ranking troops. The rank and file movement is a blanket term for informal left-leaning groups among British trade unionists, generally strenuously opposed to the union hierarchies and by them, and often facing expulsion.