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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  
/ 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

Synonym Usage

See earnest 1.

Other Word Forms

Etymology

Origin of sincere

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

Explanation

Being sincere is being genuine. If someone compliments you on your outfit, but you notice them rolling their eyes when they think you’re not looking, they probably weren't being sincere. If you've been offered a sincere thanks for something you've done, the person is probably really grateful. Sometimes when people say "thank you," they don't always mean it, but when they add the adjective sincere, the emphasis is usually for a very good reason. You may hear a charity sending out a sincere thanks to sponsors for their donations, which help keep the charity running.

Keep Reading on Vocabulary.com

Vocabulary lists containing sincere

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.

See Examples For:

Jordan Firstman’s sincere, funny and genuinely moving debut feature has him playing a queer New York underground party promoter blindsided by the arrival of the 10-year-old son previously unknown to him.

From Los Angeles Times ● Oct. 12, 2026

In a post on messaging app Telegram, gig organisers Say Agency confirmed the concerts had been cancelled with "sincere regret".

From BBC ● Oct. 1, 2026

He praised her "breadth of knowledge and passion" and called her "the ultimate breaker of the glass ceiling", adding: "She will be greatly missed and my sincere thoughts are with her family."

From BBC ● Oct. 1, 2026

"Among Quebecers there is a rare way of helping: discreet, sincere, without fanfare," he wrote in October 2025.

From Barron's ● Sep. 30, 2026

So when you’re evaluating whether she’s sincere in her belief or a lunatic, you should know she’s got more degrees, speaks more languages, and has seen more of the world than most people you know.

From "Everything Sad Is Untrue" by Daniel Nayeri

“There is no sincerer love than the love of food,” reads the slip of paper.

From Washington Post ● Apr. 21, 2015

Guarantee us peace," begged Mr. Guinness, "and Germany will find she has no sincerer and no more useful friend in the world than Britain!

From Time Magazine Archive

Another Richmond editorial said, “There will in all the earth be no sincerer mourners than the people of the southern section of this Union.”

From "Ambushed!" by Gail Jarrow

It seems to me that in these matters the sincerer we are, the better it is for all parties.

From The Fourth Estate, vol. 2 by Armando Palacio Vald?s

His Morning and Evening Hymns introduced a simpler, sincerer style of religious poetry.

From A Brief Handbook of English Authors by Oscar Fay Adams

And it’s our sincerest hope that all of Europe will follow your example.

From The Wall Street Journal ● Oct. 8, 2026

Parody, in this case, is the sincerest form of flattery.

From The Wall Street Journal ● Apr. 21, 2026

"What happened today in Teotihuacan hurts us deeply. I express my sincerest solidarity to the people affected and their families," Sheinbaum wrote.

From Barron's ● Apr. 20, 2026

Life-altering in the sincerest sense of the word, “The Mother Lode” comedically chronicles Rosebud Baker’s journey into motherhood, in real time.

From Los Angeles Times ● Dec. 10, 2025

"May I express my sincerest apologies for the illness of your mother, our queen," I say with a bow, and kiss two fingers to place at my heart.

From "The Belles" by Dhonielle Clayton

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