written request; written demand
A formal document submitted to an organization or authority to request or demand action, often used in business, government, or community contexts.
The residents submitted a written request to the city asking for park improvements.
The labor union sent a written demand for a pay raise to the company.
陳情書 is a written statement of opinion or request to a government body, often used in political or administrative contexts, similar to 要望書 but may carry a nuance of appealing for consideration rather than demanding.
Compound of 要望 (request, demand) + 書 (document). The exact historical derivation is uncertain, but the word follows a common pattern for formal documents.