Army
An army (from Latin arma "arms, weapons" via Old French armée, "armed" feminine) or land force is a fighting force that fights primarily on land. In the broadest sense, it is the land-based military branch, service branch or armed service of a nation or state. It may also include aviation assets by possessing an army aviation component. In certain states, the term army refers to the entire armed forces. Within a national military force, the word army may also mean a field army.
By convention, irregular military is understood in contrast to regular armies which grew slowly from personal bodyguards or elite militia. Regular in this case refers to standardized doctrines, uniforms, organizations, etc. Regular military can also refer to full-time status (standing army), versus reserve or part-time personnel. Other distinctions may separate statutory forces (established under laws such as the National Defence Act), from de facto "non-statutory" forces such as some guerrilla and revolutionary armies. Armies may also be expeditionary (designed for overseas or international deployment) or fencible (designed for – or restricted to – homeland defence)