[noun] [C] [UK and ANZ] [informal] - a bad mood, esp. one in which a person will not do what they are asked and is unpleasant to other peopleDon't go in unless you have to - she's in a (real) strop.And why have you got (such) a strop on (= why are you in such a bad mood), what's happened?
STROP
Meaning of STROP in English
Cambridge English vocab. Кембриджский английский словарь. 2012