떼가 · 떼를
stubborn demand, tantrum (in 떼를 쓰다)
Example
아이가 장난감을 사 달라고 떼를 썼어요.
The child threw a tantrum demanding a toy.
Word parts
Homonym warning: another 떼 means 'crowd, flock', as in 사람들이 떼로 몰려오다.
Good to know
Almost always used as 떼를 쓰다 or 떼쓰다, especially about children.