A formal proposal, request, or notification presented to someone (including offers or complaints).
労組は会社に賃上げの申し入れを行った。
The labor union made a request to the company for a wage increase.
顧客からの申し入れにより調査を開始した。
An investigation was launched following a customer's complaint/request.
市は住民からの申し入れを受けて対応を検討している。
The city is considering measures in response to a request from residents.