Definition of unofficially in US English:

unofficially

adverb

  • 1In a manner that is not officially authorized or confirmed.

    ‘the assets of the family are unofficially estimated to be $8 billion’
    • ‘The summer movie season unofficially begins during the first weekend of May.’
    • ‘I should point out that, unofficially at least, I'm wearing two hats.’
    • ‘Unofficially, the documentary has joined the massive underground market in illegal videos.’
    • ‘The dress code at the laboratory is unofficially more casual than at the rest of the company.’
    • ‘Where most detective fiction involves a city unofficially run by gangsters, here the villains are outwardly in control.’
    1. 1.1British Used to indicate strike action not called or endorsed by the union to which the strikers belong.
      ‘thousands of railwaymen struck unofficially for higher wages’
      • ‘Thousands of civil servants have defied anti-union laws to unofficially walk out of work in the last two weeks.’
      • ‘It was the first time a whole fire brigade has struck unofficially since 1977.’
      • ‘Union leaders are worried that other postal workers may strike unofficially.’
      • ‘These workers have walked out unofficially on strike as a protest against racism.’
      • ‘They're the last people you would imagine to walk out unofficially and shout at the boss.’

Pronunciation

unofficially

/ˌənəˈfiSHəlē//ˌənəˈfɪʃəli/