/ˌʌnˈnəʊn ||; ʌnˈnon/adj1 unknown (to sb) that sb does not know; without sb knowing 不为人知的；不知道的: Unknown to the boss, she went home early. 她提早回家，她的上司毫不知情。
2 not famous or familiar to other people 不著名的；默默无闻的: an unknown actress 不出名的女演员 [OPP] well known or famous 反义词为well known或famous
an unknown quantity a person or thing that you know very little about 不了解的人或事物；未知数