expression, godan verb (-ku)
be about to cry; be close to tears; whimper
Describes a state where someone, especially a child, is on the verge of crying, often with a trembling or pouting expression. The phrase is idiomatic and commonly used in everyday speech.
叱られた子供が泣きべそをかいている。
The scolded child is on the verge of tears.
彼は悔しくて泣きべそをかいた。
He was so frustrated that he almost cried.