来週
らいしゅう · raishuu · JLPT N5 · noun
week
📅 来週 = coming (来) + week (週): the week that comes next
来 (rai) means come and 週 (shuu) means week, so the word is literally the coming week. The same 来 prefix builds 来月 (raigetsu, next month) and 来年 (rainen, next year), so one pattern covers all three.
来 — pictograph of a wheat plant with grain heads
来 originally depicted a stalk of wheat with drooping grain heads, and meant 'wheat' in oracle bone script. It was later borrowed phonetically to write the unrelated verb 'to come,' which became its dominant meaning. The original 'wheat' sense was taken over by 麥 (now 麦).