IPA: /ˈmɪsɪv/
KK: /ˈmɪsɪv/
A written message or letter that is sent to someone.
She received a missive from her friend in another country.
Missive → It is formed from "missus" (the past participle of "mittere", meaning to send) and the suffix "-ive" (meaning having the nature of). The word "missive" refers to something that is sent, particularly a letter or message.
Think of something that is 'sent' ('mittere') — that's why a missive is a message or letter that is sent.