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REFERENCE

unofficial

adj.
US //ˌənəˈfɪʃəɫ// UK //ʌnəfˈɪʃəl// un·of·fi·cial
  1. 1 not formal or authorized (adj.)
    B2 Upper Intermediate

    not confirmed or approved by an organization, government, or person in charge.

    lacking formal sanction, confirmation, or authorization from a governing body or official source.

    Example

    The unofficial results of the election were shared on social media before the final count.

    Example

    Although the deal was common knowledge among the staff, it remained unofficial until the board of directors signed the final contract.
  2. 2 acting without authority (adj.)
    B2 Upper Intermediate

    doing something without having the legal right or power to do it.

    acting without the requisite legal or institutional authority; often used to describe roles or actions taken outside of formal structures.

    Example

    He acted as an unofficial advisor to the president for many years.

    Example

    The committee was criticized for its unofficial investigation, which many felt overstepped its legal boundaries and lacked transparency.
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  1. 3 not in a pharmacopeia (adj.)
    C2 Proficiency Technical Medicine

    describes a medicine or chemical that is not listed in an official medical book.

    referring to a medicinal substance or preparation not listed in a national or international pharmacopeia.

    Example

    The doctor warned that the unofficial remedy had not been tested for safety.

    Example

    The laboratory identified several unofficial compounds in the herbal supplement that were not disclosed on the product label.

    Usage

    Usually placed before the noun it modifies.
    • non pharmacopeial
Origin

From un- + official.

Word family

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