n.
- a division of 3,000–6,000 men in the ancient Roman army.
-
(the Legion)
the Foreign Legion.
- a national association of former servicemen and servicewomen, such as the Royal British Legion.
-
(a legion/legions of)
a vast number of people or things.
adj.
great in number:
her fans are legion.
Derivative
Etymology
ME: via OFr. from L. legio(n-), from legere ‘choose, levy’.