sincere
sin-SEERadjMeaning meaning what one says; free of pretense
Memory hook sin-SEER: you can SEE he means it. Theo hands Mom a crumpled crayon card that says “I LUV U,” and she can see he means every word. His card is sincere.
Her apology was sincere; she had tears in her eyes.
In context Unlike the salesman’s rehearsed compliments, the boy’s thank-you note was sincere: he had written it himself, misspellings and all, because he loved the gift.
Similar heartfelt, honest, earnest, wholehearted
Opposite insincere, false, fake
From Latin sincerus, “pure, clean, whole.”