1.
bulk purchase; lump-sum purchase; buying in one go
Purchasing goods or services all at once rather than in installments or separately. Used both for buying large quantities at a discount and for paying the full price upfront.
Usage
Used in two main contexts: (1) buying in large quantities for a discount, and (2) paying the full price at once instead of in installments (as with smartphones or electronics). Often contrasted with installment payments (分割払い).