Subduplicate \Sub*du"pli*cate\, a. (Math.) Expressed by the square root; -- said of ratios. [1913 Webster]

Subduplicate ratio, the ratio of the square roots, or the square root of a ratio; thus, the subduplicate ratio of a to b is [root]a to [root]b, or [root]a/b. [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48
 

Subduplicate \Sub*du"pli*cate\, a. (Math.) Expressed by the square root; -- said of ratios.

Subduplicate ratio, the ratio of the square roots, or the square root of a ratio; thus, the subduplicate ratio of a to b is [root]a to [root]b, or [root]a/b.

Source: Webster's Revised Unabridged Dictionary (1913)