Level 3 · word 2,313 of 20,000

unknown

/ʌnˈnoʊn/ American
  • adj. 未知的, 不熟悉的
  • n. 未知事物, 未知数
Definition
  • adj. not known or familiar to someone
  • n. something that is not known or identified
Example
The cause of the strange noise remains completely unknown.
那个奇怪声音的原因至今完全未知。