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Webster 1913 Edition
Triarian
Tri-a′ri-an
,Adj.
 [L. 
triarii
, pl
., a class of Roman soldiers who formed the third rank from the front, fr. tres
, tria
, three.] Occupying the third post or rank. 
[Obs.] 
Cowley.
 Webster 1828 Edition
Triarian
TRIA'RIAN
,Adj.