异想天开
yì xiǎng tiān kāi · HSK 7
to imagine the wildest thing
🦄 异 strange + 想 think + 天开 sky-opens = thinking so wild the heavens crack open
A four-character idiom: 异想 means odd or far-out thinking, 天开 literally sky-opens. Together they name a flight of fancy so bold it would split the sky. Used for unrealistic, fantastical schemes.
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.'
天 — 一 (one/sky) above 大 (big person)
Originally a pictograph of a person (大) with an emphasized head, representing what is above — the sky or heavens. The top stroke evolved into 一, symbolizing the vast expanse overhead. From 'sky' it extended to mean 'day,' 'heaven,' and 'nature.'
开 — two hands 廾 + door 门 (open gate)
Originally written 開, showing two hands (廾) lifting the bar (一) off a gate (門) to open it. The simplified form 开 keeps the two-hands element and drops the gate. Core meaning 'to open' extended to 'start, operate, bloom'.