legionary

noun3

1. •
   A soldier belonging to a legion; a professional soldier of the ancient Roman army.
2. •
   A member of a legion, such as the American Legion, or of any organization containing the term legion in its title (e.g. the French Foreign Legion).
3. •
   A person who is neither a citizen nor colonial/imperial subject of the state whose military they join.

adjective2

1. •
   Relating to, or consisting of, a legion or legions.
2. •
   Containing a great number.

   • Unto whom (what is deplorable in men and Christians) too many applying themselves, betwixt jest and earnest, betray the cause of truth, and insensibly make up the legionary body of error. — 1646

noun1

1. •
   a member of the Legion of Christ, a Roman Catholic religious institute