counterbrace

 

From counter- +‎ brace.

counterbrace (third-person singular simple present counterbraces, present participle counterbracing, simple past and past participle counterbraced)

1. (nautical, transitive) To brace in opposite directions.

   To counterbrace the yards is to brace the head yards one way and the after yards another.

2. (engineering, transitive) To brace in such a way that opposite strains are resisted.
   • 1890, Charles Herbert Moore, Development and Character of Gothic Architecture, Chapter 2:

     Here a, b, and c are the great ribs whose thrusts, in the direction of the arrows, are concentrated upon the pier, d, and are counterbraced by the flying buttress, e. In other words, the section through the vaulting conoid at half its vertical height gives the triangle, a, b, c, in A, and not the square, a, b, c, d, in B in the same figure.

     see diagram atop the page