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REFERENCE

unfamiliar

adj. · n.
US //ˌənfəˈmɪɫjɝ// UK //ʌnfəmˈɪliə// un·fa·mil·iar
  1. 1 strange or unknown (adj.)
    B2 Upper Intermediate

    not known or recognized because you have not seen or experienced it before.

    not known or recognized; lacking the quality of being familiar through previous encounter or experience.

    Example

    The city felt scary at first because all the streets were unfamiliar to me.

    Example

    Walking through the dense fog, he found himself in an unfamiliar neighborhood where even the architecture seemed alien and unsettling.

    Usage

    Often followed by the preposition 'to'.
  2. 2 lacking knowledge (adj.)
    B2 Upper Intermediate

    not knowing much about a particular subject or how to do something.

    not having knowledge or experience of a specific subject, system, or practice.

    Example

    I am unfamiliar with this computer program, so I might need some help.

    Example

    The new manager was largely unfamiliar with the technical nuances of the project, necessitating a comprehensive briefing from the engineering team.

    Usage

    Usually followed by the preposition 'with'.
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  1. 3 a stranger (n.)
    C2 Proficiency Literary

    a person that you do not know.

    a person with whom one is not acquainted. This nominal use is significantly less common than the adjectival form.

    Example

    The dog barked loudly at the unfamiliar standing at the gate.

    Example

    In the quiet village, the arrival of an unfamiliar was always met with a mixture of curiosity and guarded silence.

    Teacher's tip

    This noun sense is rare in modern speech; students should use 'stranger' in almost all contexts.
Origin

From un- + familiar.

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