忙 means “busy”

いそがしい · isogashii

Also: occupied, restless

Kun'yomi (Japanese reading)
いそがしい, せわしい, おそれる, うれえるさま
On'yomi (Chinese reading)
ボウ, モウ

JLPT N3 · Taught in secondary school · 6 strokes

The story

The heart (忄) beside 亡, "lost": so busy your heart goes missing. It is the same pair as 忘, forget, rearranged: in 忙しい the heart stands beside the loss, in 忘れる it sinks beneath it.

Used in 忙しい (isogashii, busy), 多忙 (tabou, extremely busy), and 大忙し (ooisogashi, rushed off one's feet)

More from How Things Feel

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Readings from KANJIDIC2, © EDRDG, CC BY-SA.