同时
tóng shí · HSK 2
at the same time
⏰ 同 (same) + 时 (time) = at the same time
同 means 'same/together' and 时 means 'time/hour'. Combined literally as 'same-time', the compound means simultaneously. Compare 同学 (same-study = classmate) and 时间 (time-interval = time).
同 — 冂 enclosure + 一 + 口 mouth
Originally depicted multiple mouths gathered under one cover or enclosure, suggesting people speaking together in agreement. From this image of voices joining, it came to mean 'same,' 'together,' or 'alike.' The shared cover symbolizes unity.
时 — sun 日 + temple/measure 寺
Originally a phono-semantic compound: 日 (sun) gives the meaning of time or season, while 寺 (shí) supplies the sound. Early forms used 之 as the phonetic before 寺 replaced it. The core sense 'season, time, hour' has stayed stable since ancient Chinese.