1.
proviso; stipulation; caveat
A clause or condition added to a document, rule, or statement that qualifies or limits the main content. Common in legal, contractual, and official documents.
2.
itemization on a receipt; description field
The line on a receipt or invoice that specifies the purpose of payment, such as "for books" or "for meeting expenses."
Usage
但し書き has two distinct uses: as a legal/formal proviso (sense 1) and as the description line on receipts (sense 2). Both senses involve writing that specifies or qualifies something.
Sense 1 (PROVISO)
In legal documents, a 但し書き begins with 但し (however) and introduces conditions, exceptions, or limitations to the main provision.
Sense 2 (RECEIPT)
When purchasing items in Japan, shops often ask how to fill in the 但し書き field. Common entries include お品代 (merchandise), 書籍代 (books), 飲食代 (food and drink).
Related Words
Compare:
注意書き (cautionary note)