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

But the song is sweet and sincere without being twee, and just as in every scenario that could go either way, we are denied the comedic pressure valve that might release a little of the squirm. — Jessica Kiang, Variety, 7 July 2026

But again, none of this is expected, and a sincere thank you is appreciated just as much. — Jessica Kozuka, Travel + Leisure, 4 July 2026

Steve Buckley says the apology seemed sincere, but MLB should levy a fine anyway. — Levi Weaver, New York Times, 2 July 2026

Pair Gratitude With Personal Updates One strategy is to send regular, personal impact updates that pair sincere gratitude with specific examples of what donors made possible. — Expert Panel®, Forbes.com, 1 July 2026

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