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Synonyms

serious

American  
[seer-ee-uhs] / ˈsɪər i əs /

adjective

  1. of, showing, or characterized by deep thought.

  2. of grave or somber disposition, character, or manner.

    a serious occasion; a serious man.

    Synonyms:
    staid, sedate, sober
  3. being in earnest; sincere; not trifling.

    His interest was serious.

    Antonyms:
    trifling, frivolous
  4. requiring thought, concentration, or application.

    serious reading; a serious task.

  5. weighty or important.

    a serious book; Marriage is a serious matter.

    Synonyms:
    grave, momentous
    Antonyms:
    trivial
  6. giving cause for apprehension; critical.

    The plan has one serious flaw.

  7. Medicine/Medical. (of a patient's condition) having unstable or otherwise abnormal vital signs and other unfavorable indicators, as loss of appetite and poor mobility: patient is acutely ill.


noun

  1. that which is of importance, grave, critical, or somber.

    You have to learn to separate the serious from the frivolous.

serious British  
/ ˈsɪərɪəs /

adjective

  1. grave in nature or disposition; thoughtful

    a serious person

  2. marked by deep feeling; in earnest; sincere

    is he serious or joking?

  3. concerned with important matters

    a serious conversation

  4. requiring effort or concentration

    a serious book

  5. giving rise to fear or anxiety; critical

    a serious illness

  6. informal worthy of regard because of substantial quantity or quality

    serious money

    serious wine

  7. informal extreme or remarkable

    a serious haircut

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Related Words

See earnest 1.

Other Word Forms

  • half-serious adjective
  • half-seriously adverb
  • nonserious adjective
  • nonseriously adverb
  • overserious adjective
  • overseriously adverb
  • quasi-serious adjective
  • quasi-seriously adverb
  • seriousness noun
  • superserious adjective
  • superseriously adverb
  • ultraserious adjective
  • ultraseriously adverb
  • unserious adjective
  • unseriously adverb

Etymology

Origin of serious

First recorded in 1400–50; late Middle English, from Middle French serieux and Latin sērius “grave, earnest” or Late Latin sēriōsus; -ous, -ose 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The change could have serious consequences for everyone from workers filing tax returns to students applying to college.

From The Wall Street Journal

“A program intended to promote treatment must never be allowed to erode accountability for the most serious and violent crimes against children,” she said in a statement online.

From Los Angeles Times

"I need surgery to remove the disease, but the waiting lists are too long. I'm told there are too many more serious cases ahead of me."

From BBC

Former treasurer Josh Frydenberg said prior to Albanese's announcement the prime minister had been told by Jewish leaders there were "serious concerns" about her appointment, without specifying what they were.

From BBC

The findings, published on January 5 in Nature, raise serious challenges for widely accepted models of galaxy cluster formation.

From Science Daily