usage
Covers both the geometric concept (a non-vertical, non-horizontal line) and the typographic '/' symbol. For the backslash '\' specifically, Chinese uses 反斜线 (fǎn xiéxiàn) or 反斜杠 (fǎn xiégàng). The everyday computer-keyboard reading is often 斜杠 (xiégàng, 'oblique stick').
culture
斜杠 (the slash itself) has spawned the popular term 斜杠青年 (xiégàng qīngnián) - 'slash youth' - for young professionals with multiple careers (e.g. designer/writer/podcaster), borrowed from American author Marci Alboher's concept of slash careers.
