To indirectly criticize or scold someone by ostensibly directing one's words at another person or thing; to make an oblique attack.
小明虽然表面上在批评班长，但大家心里都明白他这是指冬瓜骂葫芦，真正不满的是学习委员。
Although Xiao Ming was seemingly criticizing the class monitor, everyone understood that he was actually indirectly complaining about the study committee member.
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