sincere

adjective

sin·​cere sin-ˈsir 

sən-

sincerer; sincerest

1

a

: free of dissimulation : honest

a sincere interest

b

: free from adulteration : pure

a sincere doctrine

sincere wine

2

: marked by genuineness : true

sincereness noun

Synonyms of sincere

• genuine
• heartfelt
• unfeigned
• honest
• unaffected

Choose the Right Synonym for sincere

sincere, wholehearted, heartfelt, hearty, unfeigned mean genuine in feeling.

sincere stresses absence of hypocrisy, feigning, or any falsifying embellishment or exaggeration.

a sincere apology

wholehearted suggests sincerity and earnest devotion without reservation or misgiving.

promised our wholehearted support

heartfelt suggests depth of genuine feeling outwardly expressed.

expresses our heartfelt gratitude

hearty suggests honesty, warmth, and exuberance in displaying feeling.

received a hearty welcome

unfeigned stresses spontaneity and absence of pretense.

her unfeigned delight at receiving the award

Examples of sincere in a Sentence

He sounded sincere in his promises.

She seemed sincere in her commitment to finish school.

She has a sincere interest in painting.

He showed a sincere concern for her health.

He made a sincere attempt to quit smoking.

Please accept our sincere thanks.

Recent Examples on the Web

Munson, as his final choice, proves that his apologies were sincere. —Bryan Alexander, USA Today, 14 Nov. 2025

Carol sees these as temporary coping mechanisms rather than sincere, life-sustaining joy. —Kathryn Vanarendonk, Vulture, 14 Nov. 2025

But the Russian supermodel is completely sincere. —Michelle Lee, PEOPLE, 14 Nov. 2025

Asked for just a few nice lines about the director for IndieWire, OutFest Next’s top trio of tastemakers — Sheryl Santacruz, Daniel Cooke, and Gabi Grossman, all familiar festival circuit faces with real warmth behind them — sent an effervescent text wall of sincere and complex praise via email. —Alison Foreman, IndieWire, 11 Nov. 2025

Word History

Etymology

Middle French, from Latin sincerus whole, pure, genuine, probably from sem- one + -cerus (akin to Latin crescere to grow) — more at same, crescent

First Known Use

1533, in the meaning defined at sense 1a

Rhymes for sincere

• adhere
• ameer
• amir
• appear
• arrear
• astir
• austere
• career
• cashier
• cohere
• compere
• emir

Kids Definition

sincere

adjective

sin·​cere sin-ˈsi(ə)r 

sincerer; sincerest

1

: trustworthy, straightforward

a sincere friend

2

: genuine sense 1, real

a sincere interest in painting

sincerely adverb

sincerity

-ˈser-ət-ē, 

-ˈsir-

noun