\begin{definition}[Definition:Euclid's Definitions - Book V/10 - Triplicate Ratio]
{{EuclidSaid}}
:''When four magnitudes are $<$ continuously $>$ proportional, the first is said to have to the fourth the '''triplicate ratio''' of that which it has to the second, and so on continually, whatever be the proportion.''
{{EuclidDefRef|V|10|Triplicate Ratio}}
\end{definition}