Level 4 · word 5,383 of 20,000

unofficial

/ˌʌnəˈfɪʃəl/ American
  • adj. 非官方的, 非正式的
Definition
  • adj. not official or approved by an authority
Example
There is an unofficial rule that new employees buy the coffee.
有一条不成文的规定:新员工要请大家喝咖啡。