The Collaborative International Dictionary of English v.0.48:

Legionary \Le"gion*a*ry\ (-[asl]*r[y^]), a. [L. legionarius: cf.
   F. l['e]gionnaire.]
   Belonging to a legion; consisting of a legion or legions, or
   of an indefinitely great number; as, legionary soldiers; a
   legionary force. "The legionary body of error." --Sir T.
   Browne.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Legionary \Le"gion*a*ry\ (l[=e]"j[u^]n*[asl]*r[y^]), n.; pl.
   Legionaries (-r[i^]z).
   A member of a legion. --Milton.
   [1913 Webster]

WordNet (r) 3.0 (2006):

legionary
    n 1: a soldier who is a member of a legion (especially the
         French Foreign Legion) [syn: legionnaire, legionary]

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "legionary":
   Amazon, air serviceman, brave, cannon fodder, fighting man,
   food for powder, halberdier, hoplite, man-at-arms, military man,
   navy man, pikeman, rifle, rifleman, serviceman, soldier, spearman,
   warrior, warrioress