godan verb (-mu)
shock grain; bind and stack sheaves
Agricultural term for gathering harvested grain stalks into sheaves and stacking them upright in a field to dry. Rare in modern everyday conversation.
昔は稲を刈った後、田んぼで束ね積んで乾かした。
In the past, after cutting the rice, they shocked it in the field to dry.
Compound of 束ね (bundle) and 積む (stack). The exact historical derivation is uncertain, but the word is formed from these two common verbs.