soldier

[1]	serve (in the army)
[2]	soldier on , continue , persist , persevere , endure , drive , keep going , keep on/at , grind , drudge

[1]	serviceman , servicewoman , recruit , fighter , infantryman , foot-soldier , trooper , warrior , military man , man-at-arms , (Brit) Tommy (Atkins) , (US) enlisted man/woman , (Colloq) (Brit) squaddie , (US) GI/G.I.(Joe) , (Old-fashioned) doughboy
[2]	fighter , stalwart , supporter , militant