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Synonyms

sincere

American  
[sin-seer] / sɪnˈsɪər /

adjective

sincerer, sincerest

  1. free of deceit, hypocrisy, or falseness; earnest.

    a sincere apology.
    Synonyms:
    unaffected, guileless, open, honest, candid, frank
    Antonyms:
    false

  2. genuine; real.

    a sincere effort to improve; a sincere friend.
    Antonyms:
    false

  3. pure; unmixed; unadulterated.

  4. Obsolete. sound; unimpaired.

sincere British  
/ sɪnˈsɛrɪtɪ, sɪnˈsɪə /

adjective

  1. not hypocritical or deceitful; open; genuine

    a sincere person

    sincere regret

  2. archaic pure; unadulterated; unmixed

  3. obsolete sound; whole

"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

  • quasi-sincere adjective
  • quasi-sincerely adverb
  • sincerely adverb
  • sincereness noun
  • sincerity noun

Etymology

Origin of sincere

First recorded in 1525–35; from Latin sincērus “pure, clean, untainted”

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.

That’s what Auf der Maur’s roommate told her the night she came home after thinking that she had offered a sincere but thoughtful declination to the suggestion that she become the bass player in Hole.

From Salon • Mar. 24, 2026

Doherty said while the idea began as a joke, the finished video takes on a more sincere tone.

From BBC • Mar. 23, 2026

"You'd have to have a sincere commitment by both sides to make this work," he added.

From Barron's • Mar. 22, 2026

Traditionally, Irish culture values goodbyes that are warm, friendly and sincere.

From The Wall Street Journal • Mar. 13, 2026

There was something rather sincere and pathetic about her going off to a shop in London and buying me these books because she knew I was fond of painting.

From "Rebecca" by Daphne du Maurier

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.