空想
くうそう · kuusou · JLPT N2 · noun
reverie
☁️ 空 = empty/sky + 想 = thought: a thought floating in empty air, a daydream
空 means empty or sky, and 想 means thought or longing. Together they describe a thought drifting with nothing solid behind it, like a cloud in open sky.
空 — cave radical 穴 + 工 (phonetic)
Originally a phono-semantic compound: 穴 (cave, hole) gives the meaning of emptiness or hollow space, while 工 supplies the sound. The earliest sense was 'hole' or 'cavity,' which extended to 'empty,' 'sky,' and 'in vain.' The reading kòng (4th tone) specifically means 'free time' or 'vacancy.'
想 — heart 心 + 相 (xiāng, phonetic)
想 is a semantic-phonetic compound. The heart radical 心 at the bottom carries the meaning, since classical Chinese located thought and feeling in the heart. The top component 相 (xiāng) supplies the sound, and over time the character settled into the senses 'to think,' 'to want,' and 'to miss.'