entries → 懈
TSUMUGU · C1 (est.) · 字
懈 character · C1 (est.)
懈 ＝ 忄 ＋ 解
ㄒㄧㄝˋ · xiè
verb/adj — to slack off; lax, idle

字源 FORM — what the parts do

忄義the heart, will
解聲jiě — to untie, loosen; gives the soundthe j slid to x
{j,q,x}Ijiě → xiè — the {j,q,x} crossing; tone holds
The will (忄) comes untied — to slack off. 解 jiě, to loosen, carries the sound, worn from j to x; and a loosened heart is exactly what slacking is. So 鬆懈 goes loose, 不懈 stays tight.

故事 STORY — a scene to remember it by

繃緊的心（忄）忽然解（解）開了結，整個人鬆下來。
The taut heart (忄) lets its knot come undone (解), and the whole man goes slack.
字源記憶法
意 · Meanings
(本義)懈怠、鬆懈— to slack off; lax常用
→不懈— unflagging — the slack refused
(本義) original meaning · → ⇒ each arrow = one more step of extension
關 · Related
解jiěthe phonetic, to untie — 懈 binds the heart 忄 to it for the loosened will邂xièsame 解 sound, but with 辶 — to chance upon (邂逅)