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REFERENCE

serious

adj. · adv.
US //ˈsɪɹiəs// UK //sˈiəɹɪəs// se·ri·ous
  1. 1 not joking or funny (adj.)
    A2 Elementary

    quiet and thinking carefully, without laughing or making jokes.

    characterized by a grave or somber disposition; lacking humor or levity in manner.

    Example

    The teacher looked very serious when he told the students to be quiet.

    Example

    The lead investigator maintained a serious expression throughout the briefing, refusing to indulge in the lighthearted banter of his colleagues.
  2. 2 important or dangerous (adj.)
    A2 Elementary

    important and needing a lot of thought because it could cause problems.

    having significant or dangerous consequences; not trivial or slight.

    Example

    The doctor said it was a serious injury and she needed to stay in the hospital.

    Example

    The board of directors met to discuss the serious financial implications of the failed merger, acknowledging that the company's future was at stake.
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  1. 3 sincere and honest (adj.)
    B1 Intermediate

    really meaning what you say and not just pretending or playing.

    acting in earnest; sincerely intending to carry out a stated plan or promise.

    Example

    Are you serious about moving to another country for work?

    Example

    Despite his reputation for sarcasm, he was entirely serious when he offered to fund the local community project.
    • insincere
    • fippant
  2. 4 very committed (adj.)
    B1 Intermediate

    giving a lot of time and energy to an activity because you care about it.

    deeply interested in or devoted to a particular activity or subject.

    Example

    She is a serious student who spends every weekend in the library.

    Example

    As a serious collector of rare manuscripts, he spent decades scouring European auctions to complete his primary research library.
  3. 5 seriously (adv.)
    C1 Advanced Informal Dialect

    used in some phrases to mean 'in a serious way'.

    functioning as an adverbial modifier, particularly in fixed collocations like 'take serious' or 'mean serious'.

    Example

    You shouldn't take him too serious when he is in a bad mood.

    Example

    The foreman warned the crew that the safety inspector would take any violations serious, regardless of past performance.

    Usage

    In standard English, 'seriously' is required; this form is restricted to specific informal or regional speech patterns.
Origin

From Middle English seryows, from Old French serieux, from Medieval Latin sēriōsus, an extension of Latin sērius (“grave, earnest, serious”), from Proto-Indo-European *swer- (“heavy”). Cognate with German schwer (“heavy, difficult, severe”), Old English swǣr (“heavy, grave, grievous”). More at swear, sweer.

Word family

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