noun
express delivery mail; special delivery post
Abbreviation of 速達郵便. Refers to mail sent by express or special delivery service.
この書類は速達便で送ってください。
Please send these documents by express delivery.
速達郵便 is the full, formal term; 速達便 is the common abbreviation.
Compound of 速達 (express delivery) and 便 (mail, service). Abbreviation of 速達郵便.