round on

US /raʊnd ɑːn/
UK /raʊnd ɑːn/
"round on" picture
1.

襲いかかる, 攻撃する

to turn on someone suddenly and attack them, either verbally or physically

:
She suddenly rounded on him, accusing him of lying.
彼女は突然彼に襲いかかり、嘘つきだと非難した。
The crowd rounded on the speaker after his controversial remarks.
彼の物議を醸す発言の後、群衆は演説者に襲いかかった