Traduction :
lit. to flick dust off sb's cap (idiom); to celebrate an official appointment; to congratulate and celebrate (promotion, graduation etc)
Référence :
弹冠：掸去帽子上的灰尘，准备做官。指官场中一人当了官或升了官，同伙就互相庆贺将有官可做。
Origine :
《汉书·王吉传》：“吉与贡禹为友，世称‘王阳在位，贡禹弹冠。’”宋·苏洵《管仲论》：“一日无促，则三子者，可以弹冠而相庆矣。”
Annotation :
弹冠相庆1
1. tánguānxiāngqìng :
[EN] lit. to flick dust off sb's cap (idiom); to celebrate an official appointment; to congratulate and celebrate (promotion, graduation etc)
