A missive is a letter or written message, especially one that's formal or official. When a principal sends a missive to parents about new school policies, it sounds more serious than just saying “a note.” When a general sends a missive to his troops during wartime, he's communicating important orders or information.

Today, people sometimes use it playfully to make ordinary messages sound grand. You might jokingly call your friend's text message a missive if it's unusually long or dramatic: “I received your missive about yesterday's cafeteria disaster.”

While we mostly use missive for written communication, it carries a weight that words like “note” or “email” don't. A missive usually contains something important: news, instructions, or information that matters. When a historical figure like Thomas Jefferson or Abraham Lincoln wrote a missive, it might have shaped events or revealed their thinking about crucial decisions. The word reminds us that written messages, even today, can carry real significance.