余切

cotangent (of angle), written cot θ or ctg θ

surname Yu

(archaic) I / me / variant of 餘|余[yu2], surplus

extra / surplus / remaining / remainder after division / (following numerical value) or more / in excess of (some number) / residue (math.) / after / I / me

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]