what's the meaning of "Overnight Rate"

Overnight Rate即隔夜利率，也叫同业拆借利率，是银行间为弥补短期资金不足而相互贷款的日利率

大银行间借贷款的利率.一般每月更新.
同时也指中央银行与某些特殊组织银行间的借贷利率.

同业拆借利率是在经济中测量货币流动性的手段.流动性低或者银行间缺乏信任时该利率会猛涨.

就是银行间的同业拆借利率，隔夜利率，日拆利率，隔夜拆借利率。

When a bank,say bank A, needs to increase reserve in central bank but it hasn't enough, it'll lend from another bank,say bank B. B agrees, but it wants an interest. The rate of the interest is overnight rate. It gets its name because A usually has to give back the money after only 24 hours.

同业拆借利率

就是银行间的同业拆借利率，隔夜利率，日拆利率，隔夜拆借利率。