What is the name of two points that share one coordinate?

Question

Is there an adjective to characterize two points in $\mathbb R^2$ that have the same value for one of the coordinates?

Answer 1

Two points $(x_1, y_1), (x_2, y_2) \in \mathbb R^2$ such that $x_1 = x_2$ can be said to lie on the same vertical line $x = x_1$, and similarly, if they are such that $y_1 = y_2$, the points can be said to lie on the same horizontal line $y = y_1$.

But I don't believe there is any word to fill in the blank to describe them as ___points: Perhaps "vertically aligned" points in the first case, and "horizontally aligned" points, in the second case? But this characterization is rather informal.