To purchase or buy in (often large quantities or for inventory); commonly used in business or procurement contexts.
小売店は新商品の在庫を卸業者から買い入れた。
The retailer bought in stock of the new product from the wholesaler.
古本屋が珍しい本を買い入れたと聞いた。
I heard that the used bookstore bought in a rare book.
市場は地元の魚を直接買い入れている。
The market purchases local fish directly.