How to Write 悃 (kǔn) — Meaning “Sincere or heartfelt.”

Imagine your heart (忄) is 'trapped' (困) inside a box because you are so full of sincere feelings that they cannot escape. The image of a heart locked in a square helps you recall that 悃 means sincere or heartfelt.

The left radical 忄 is written as a vertical stroke for the heart, then two dots — do not connect the dots to the vertical line. On the right, 困 has an outer box (囗) which must fully enclose 木 (tree), and the bottom horizontal stroke of 囗 should be slightly longer than the top to balance the character.

Unlike 悃 (sincere), 怊 (chāo) means 'sad' or 'grieving', and 怍 (zuò) means 'ashamed' or 'embarrassed'. Visually, 悃 has the right side 困 (box with tree), 怊 has the right side 召 (summon), and 怍 has the right side 乍 (sudden) — so you can tell them apart by their different right components.

悃 is a formal, literary character rarely used in daily speech, mostly found in written expressions like 诚悃 (sincere sincerity) and 谢悃 (sincere thanks), especially in respectful letters or official documents. It carries a classical, polite tone — similar to using 'sincerely' in English at the end of a formal letter.

Common words containing 悃 include: 诚悃 (chéng kǔn) — sincerity (formal); 谢悃 (xiè kǔn) — sincere gratitude; 悃愊 (kǔn bì) — Sincere and genuine..