ENGLISH
REFERENCE

mysterious

adj.
US //mɪˈstɪɹiəs// UK //mɪstˈiəɹɪəs// mys·te·ri·ous
  1. 1 strange and unknown (adj.)
    B1 Intermediate

    strange, unknown, or difficult to understand or explain.

    relating to or being a mystery; difficult or impossible to understand, explain, or identify.

    Example

    A mysterious light appeared in the sky late last night.

    Example

    The detectives were baffled by the mysterious disappearance of the painting, as the security alarms had never been triggered.
  2. 2 secretive behavior (adj.)
    B2 Upper Intermediate

    behaving in a way that shows you are keeping a secret.

    deliberately enigmatic or evasive in behavior or speech, often to provoke interest or hide information.

    Example

    He was being very mysterious about where he went last weekend.

    Example

    She gave him a mysterious smile and refused to say another word about her plans for the upcoming merger.

    Usage

    often used to describe a person's expression or tone of voice
Origin

From Middle English *misterius (implied in misteriusly), probably partly from Middle French mystérieux and partly from Latin mystērium + -ous. By surface analysis, mystery + -ous.

Word family

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