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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

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.

The need to come together across the political divide to find common solutions to shared concerns depends primarily on a sincere desire for real dialogue.

From Salon • May 12, 2026

Blasting from my car speaker, Dr. Becky sounds sincere to the point of tearful.

From Slate • May 10, 2026

It is our sincere hope that this brings closure and allows all involved to move forward constructively and in peace, including a respectful environment online.”

From Los Angeles Times • May 4, 2026

"He's a sincere, quiet gentleman. A very intelligent guy," they said.

From BBC • Apr. 30, 2026

She was old, of course, but she didn’t have warts or green teeth and her smile was sincere and inviting.

From "Rump: The (Fairly) True Story of Rumpelstilskin" by Liesl Shurtliff