/ 9Qn5nEUn; Qn`non/ adj ~ (to sb) 1 not known or identified 未知的; 不详的; 未被认识的; 未认出的: The side-effects of the drug are as yet unknown (toscientists). 这种药的副作用（科学家）尚未发现. * Unknownforces were at work to overthrow the government. 有些尚未查明的势力正在活动图谋推翻政府.
not famous or well known; unfamiliar 不出名的; 不闻名的; 不熟悉的; 陌生的: The star of the film is a previously unknown actor. 这部电影里的明星以前是个默默无闻的演员.
(idm 习语) an ,unknown `quantity person or thing that one has no experience of and whose nature, significance, etc one therefore cannot predict 不了解的人或事物（因而无法估量其特点﹑ 重要性等）: The new sales director is still a bit of an unknown quantity. 新来的销售部主任大家还不大了解. unknown to sb without the knowledge of sb 不为某人所知: Quite unknown to me, she'd gone ahead and booked the holiday. 在我完全不了解的情况下, 她已先行办好了度假的预订手续.
> unknown n (a) (usu 通常作 the unknown) [sing] thing, place, etc that is unknown 未知的或不了解的事物﹑ 地方等: a journey into the unknown 前往陌生地方之行 * fear of the unknown 对不了解的事物的恐惧. (b) [C] person who is not well known 不出名的人: The leading role is played by a complete unknown. 演主角的是一个毫无名气的演员. (c) [C] (mathematics 数) quantity that is not yet determined 未知元; 未知数; 未知量: x and y are unknowns. x和y代表两个未知数.