Missive

Part of speech: noun (n.)

1. That which is sent; a writing containing a message.

2. One who is sent; a messenger. [Obs.] Shak.

Part of speech: adjective (a.)

1. Specially sent; intended or prepared to be sent; as, a letter missive. Ayliffe.

2. Missile. "The missive weapons fly." Dryden. Letters missive, letters conveying the permission, comand, or advice of a superior authority, as a sovereign. They are addressed and sent to some certain person or persons, and are distinguished from letters patent, which are addressed to the public.