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

As Ross added some sincere words of praise and a salute for Kraft, the Patriots owner was shown smiling in the crowd. —Los Angeles Times, 29 Apr. 2026

If imitation is the sincerest form of flattery, OpenAI’s actions are especially telling. —Matteo Wong, The Atlantic, 28 Apr. 2026

Hyper-self-aware, but also simultaneously sincere. —New York Times, 28 Apr. 2026

Written through the intuitive and curious perspectives of 12-year-olds, this memorable project manages to capture both their developing skills and innocent but sincere efforts to understand another generation. —Denise Crosby, Chicago Tribune, 24 Apr. 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