> I have no objection to a term like “right angle” if it is relevant to the problem and makes it easier to discuss. It’s not terminology itself that I object to

> I have no objection to a term like “right angle” if it is relevant to the problem and makes it easier to discuss. It’s not terminology itself that I object to, it’s pointless unnecessary terminology. Yet, what about orthogonal, normal, and perpendicular? How does being [vertically] (up)right relate to the angle of y=-|x|? Why line instead of isodi(a)gon(al)? Why parallel instead of paraisodiagonal? Are there abnormal, prostrate or for that matter left angles? Would not this angle of the normal line come before the definition of an angle formed by two straight lines?