noun
inkstone-washing event before Tanabata
A traditional custom where schoolchildren wash their inkstones, brushes, and desks the night before Tanabata (July 7th) to pray for academic success. Rare term; mostly known in historical or regional contexts.
See also: 七夕
七夕の前夜、子どもたちは硯洗いをして学業成就を祈った。
On the night before Tanabata, children performed the inkstone-washing ritual to pray for success in their studies.