legion

Short definition from Wiktionary

Adjective

1. 1
   Numerous; vast; very great in number.

Noun

1. 1
   The major unit or division of the Roman army, usually comprising 3000 to 6000 infantry soldiers and 100 to 200 cavalry troops.
2. 2
   A combined arms major military unit featuring cavalry, infantry, and artillery, including historical units such as the British Legion, and present-day units such as the Spanish Legion and the French Foreign Legion.
3. 3
   A large military or semi-military unit trained for combat; any military force; an army, regiment; an armed, organized and assembled militia.
4. 4
   A national organization or association of former servicemen, such as the American Legion.
5. 5
   A large number of people; a multitude.
6. 6
   A great number.
7. 7
   A group of orders inferior to a class; in scientific classification, a term occasionally used to express an assemblage of objects intermediate between an order and a class.

Verb

1. 1
   To form into legions.

Proper noun

1. 1
   Ellipsis of American Legion.