曾经
céngjīng · HSK 3
one time
⏳ 曾 = once/former + 经 = pass through; together: have passed through once
曾 (céng) on its own means 'once' or 'formerly', and 经 (jīng) means 'to pass through' or 'undergo'. Combined, 曾经 marks an action that was experienced at some point in the past.
曾 — top 八 + 田-like body + 日 (steamer pictograph)
曾 originally pictured a tiered bamboo steamer with rising vapor, the ancestor of 甑 'steamer pot.' It was borrowed phonetically for the grammatical meanings 'once, formerly' (zēng) and 'great-grand-' in kinship terms. Later 甑 was created with the 瓦 'tile/pottery' radical to keep the original cooking-vessel sense.
经 — silk radical 纟 + 巠 (underground stream)
Originally written 經, combining the silk radical 糸 with 巠, depicting vertical threads on a loom. The core meaning was 'warp threads,' which extended to 'pass through,' 'classic text,' and 'manage.' The phonetic 巠 also suggests the sound.