正切

(math.) tangent (trigonometric function)

first month of the lunar year

straight / upright / proper / main / principal / to correct / to rectify / exactly / just (at that time) / right (in that place) / (math.) positive

to cut / to slice / tangent (math)

definitely / absolutely (not) / (scoffing or dismissive interjection) Yeah, right. / Tut! / to grind / close to / eager / to correspond to / see also 反切[fan3 qie4]