extremely rare; the only one of its kind; (very) unique ? 新的一輩繼他們的父親或者母親之后成為作家的，可以說(shuō)～，…… (秦牧《兩代人》) It is extremely rare for one of the younger generation to follow his father’s or mother’s example and become a writer. …
絕無(wú)僅有jué wú jǐn yǒu
比喻非常稀有。unique, the only one of its kind, one and the only one