unbeknown
🇺🇸
/ˌʌnbɪˈnəʊn/
🇬🇧
/ˌʌnbɪˈnəʊn/
adjective
R
without someone's knowledge or awareness
Unbeknown to him, his friends had planned a trip.
他不知道，他的朋友们计划了一次旅行。
translation
未知