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serious - thesaurus entry
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90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.

adjective
  1. 1
    bad or dangerous enough to make you worried

    *American English synonyms or related words for this sense of serious*

    Dangerous or harmful: dangerous, harmful, disastrous, damaging, risky, hazardous, unsafe, ruinous, perilous, injurious... more
  2. 2
    important and deserving attention

    *American English synonyms or related words for this sense of serious*

    Important: important, major, key, serious, vital, crucial, significant, fundamental, central, meaningful... more
  3. 3
    meaning what you say or do, and not making a joke

    *American English synonyms or related words for this sense of serious*

    Serious and humourless: serious, in earnest, substantial, sober, solemn, stolid, deep, funereal, humorlessly, officious... more
  4. 4
    careful and detailed

    *American English synonyms or related words for this sense of serious*

    Careful and cautious: careful, cautious, thorough, painstaking, systematic, organized, meticulous, methodical, exact, provident... more
  5. 5
    someone who is serious thinks carefully about things and does not laugh much

    *American English synonyms or related words for this sense of serious*

    Serious and humourless: serious, in earnest, substantial, sober, solemn, stolid, deep, funereal, humorlessly, officious... more
    1. a.
      appearing worried or upset

      *American English synonyms or related words for this sense of serious*

      Feeling worried and nervous: worried, nervous, upset, anxious, uneasy, tense, alarmed, on edge, frightened, troubled... more
  9. 9
    informal extreme, or large in amount

    *American English synonyms or related words for this sense of serious*

    Words used to describe large amounts and quantities: substantial, considerable, extensive, enormous, huge, great, large, high, big, widely... more

derived word

seriousness

noun

These are synonyms and/or related words for serious in the American English Thesaurus. View synonyms and/or related words for serious in the British English Thesaurus.

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