proper name · the complex numeral for four, used in financial contexts to prevent fraud

支票上的大写金额需写成肆万圆。

noun · a shop, marketplace, or place of business (literary)

路边有很多酒肆供行人歇脚。

adjective · acting without restraint, wanton, or reckless

他在公共场合表现得非常放肆。