1.
small amount; small-scale; small-lot (especially of transactions)
Used in business and finance to describe small-sized transactions, accounts, or cash. The standard pair is 小口 ('small-lot') vs. 大口 ('large-lot'), applied to orders, customers, deposits, donations, and cash handling.
2.
cut end (of a log, board, or bundle); the surface where something has been cut
The flat surface exposed when a log, piece of lumber, vegetable, bundle of paper, or similar object is cut. In cooking, 小口切り means cutting a long item (green onions, cucumbers, etc.) crosswise into thin rounds.
3.
edge (of a book); the three non-spine edges of a bound book
In bookbinding, the three edges of a book other than the spine — top, bottom, and fore-edge. The fore-edge is sometimes specifically called the 前小口.
Compound of 小 ('small') and 口 ('mouth; opening; end'), with sequential voicing turning くち into ぐち. The sense development goes from the concrete 'small opening/end (of a cut object)' (sense 2) to the figurative business sense (sense 1). Sense 3 is a bookbinding specialization of sense 2.
Usage
- Sense 1 is the most frequent in modern text, especially in finance and business: 小口現金 ('petty cash'), 小口融資 ('small loan'), 小口預金 ('small-lot deposit').
- The paired contrast with 大口 is very productive: 大口注文 / 小口注文 ('large/small order').
- Sense 2 survives prominently in the cooking term 小口切り, one of the basic cutting methods taught in every Japanese cookbook.
- Sense 3 is specialist vocabulary used by publishers, bookbinders, and book lovers.
Common collocations
- 小口現金: petty cash
- 小口取引: small-lot transaction
- 小口融資: small loan
- 小口顧客: small-scale customer
- 小口切り: thin round-slice cutting (cooking)
- 本の小口: edge of a book
Similar words
- 大口: large-lot; large-scale — the direct antonym for sense 1.
- 少額: small amount (of money) — near-synonym for sense 1 when referring specifically to money, but without the 'lot size' nuance.
- 断面: cross section; cut surface — near-synonym for sense 2, more technical and general.
- 小銭: small change; coins — refers to small-denomination money; distinct from 小口 which is about transaction size, not denomination.