1530s, "without being aware," from un- (1) "not" + aware + adverbial genitive -s. Meaning "without being noticed" is recorded from 1660s. Form unaware is recorded from 1590s.
双语例句
1. Investors and currency dealers were caught completely unawares by the Bundesbank's action.
投资者和外汇交易商被德意志联邦银行的这一举措打了个措手不及。
来自柯林斯例句
2. Sometimes our expectations sneak up on us unawares.
