noun
detailed statement; specification sheet; itemized list
Refers to a written document that breaks down details, such as an invoice, specification sheet, or itemized account. Common in business and administrative contexts.
請求書と一緒に明細書も送ってください。
Please send the detailed statement together with the invoice.
工事の明細書を確認してから見積もりを承認した
I approved the estimate after checking the specification sheet for the construction work.
内訳 means 'breakdown' or 'itemization' and focuses on the categorized components of a total. 明細書 is the physical or digital document that presents such a breakdown.
Compound of 明細 (めいさい, 'details') + 書 (しょ, 'document'). 明細 is itself a combination of 明 (clear) and 細 (detailed).