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Tetsuya Ito
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(Since I usually use left-orderings, the following answer uses left-orderings)

No, when $<$ is a left-ordering which is not a bi-ordering then you can always find elements $x,y,z$ with $x <z $ and $y<z$ such that $xy>z^2$.

To see this, since $<$ is not a bi-ordering we can always find an element $a,b$ such that $1<a$ but $b^{-1}ab <1$ (so $ab < b < a^{-1}b$). Now $a^{-2} < 1$, $ab < b$ but $(a^{-2})(ab) = a^{-1}b > b$.

On the other hand, it should be mentioned that somewhat related property holds for Conradian orderings; if < is a Conradian left-ordering, then $b < ab^{2}$ holds for every $1<a,1<b$. This is stated and proved in Proposition 3.7 of On the dynamics of (left) orderable groups

Tetsuya Ito
  • 548
  • 2
  • 10