in·fan·try /ˈɪnfəntri/
  步兵,步兵團
  In·fan·try n.
  1. A body of children. [Obs.]
  2. Mil. A body of soldiers serving on foot; foot soldiers, in distinction from cavalry.
  ◄ ►
  infantry
       n : an army unit consisting of soldiers who fight on foot;
           "there came ten thousand horsemen and as many fully-armed
           foot" [syn: foot]