counter brace

CIDE DICTIONARY

counter brace,  

•  The brace of the fore-topsail on the leeward side of a vessel.  [1913 Webster]
•  A brace, in a framed structure, which resists a strain of a character opposite to that which a main brace is designed to receive.  [1913 Webster]

  " In a quadrilateral system of bracing, the main brace is usually in the direction of one diagonal, and the counter brace in the direction of the other. Strains in counter braces are occasioned by the live load only, as, in a roof, by the wind, or, in a bridge, by a moving train."  [1913 Webster]