alternate angle

剑桥词典

one of two equal angles on opposite sides of a line that crosses two usually parallel lines (= lines that are always the same distance apart ), and on opposite sides of those lines
錯角，交錯角（交錯角是兩個相等的角之一：平行的兩條線被第三條直線所截，這第三條直線的兩側就形成兩個相等的交錯角，兩條平行線的兩側也各形成兩個交錯角）
比較
corresponding angle 返回 alternate angle