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

The intimacy that develops between Carol and Zosia in this episode is sincere yet conditional, because Carol is still pumping Zosia for information. —Scott Tobias, Vulture, 19 Dec. 2025

Bruce, my sincere apology for 40 years of mangling your songs in the car. —Mike Fleming Jr, Deadline, 11 Dec. 2025

With a tone that oscillates between sincere attempts at horror filmmaking, and spoofable internet culture that barely looks like its trying, the result really works for those who wanted it. —Alison Foreman, IndieWire, 8 Dec. 2025

This fall/winter, be sincere, be self-serious, be studious. —Lizz Schumer, PEOPLE, 7 Dec. 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