Definition:Apotome of Medial/Annex

Definition
LLet $a, b \in \set {x \in \R_{>0} : x^2 \in \Q}$ be two rationally expressible numbers such that $a > b$.

Let $a - b$ be an apotome of a medial.

The real number $b$ is called the annex of the apotome of a medial.