The Collaborative International Dictionary of English v.0.48:

Cader \Ca"der\, n.
   See Cadre.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Cadre \Ca"dre\, n. [F. cadre, It. quadro square, from L.
   quadrum, fr. quatuor four.] (Mil.)
   The framework or skeleton upon which a regiment is to be
   formed; the officers of a regiment forming the staff.
   [Written also cader.]
   [1913 Webster]