片道
かたみち · katamichi · JLPT N2 · noun
one-way (trip)
🛣️ 片 = one side + 道 = road: travel down one side only, so one-way
片 means one side or one piece, and 道 means road or way. 片道 is a single leg of a journey, one direction only, as opposed to 往復 (round trip).
片 — right half of 木 (tree split vertically)
Pictograph showing the right half of a tree 木 split down the middle, depicting a thin slice or slab of wood. From this came the meanings 'slice,' 'flat thin piece,' and by extension 'sheet' or 'card.' Its mirror image 爿 represents the left half.
道 — 辶 (walk) + 首 (head)
Originally a compound of 辶 'walk/movement' and 首 'head', depicting a path one walks while looking ahead. The literal sense 'road, way' extended metaphorically to 'method, doctrine, the Way (Dao)'. This philosophical meaning became central in Daoist and Confucian thought.