from
The Collaborative International Dictionary of English v.0.48
Sesquiplicate \Ses*quip"li*cate\, a. [Sesqui- + plicate.]
(Math.)
Subduplicate of the triplicate; -- a term applied to ratios;
thus, a and a' are in the sesquiplicate ratio of b and b',
when a is to a' as the square root of the cube of b is to the
square root of the cube of b', or
a:a'::[root]b^{3}:[root]b'^{3}.
[1913 Webster]
The periodic times of the planets are in the
sesquiplicate ratio of their mean distances. --Sir I.
Newton.
[1913 Webster]