What green mail means

"Green Mail" is a term that has been used in various contexts, but I'll provide you with a few possible meanings:

1. Environmental Email: In the context of environmentalism, "Green Mail" might refer to an email campaign or newsletter that focuses on eco-friendly topics, sustainability, and environmental issues.
2. Green Card Lottery: In the context of immigration, "Green Mail" might refer to a newsletter or email service that provides information and updates on the US Green Card Lottery, also known as the Diversity Visa Program.
3. Spam Email: In a more negative sense, "Green Mail" might be used to describe a type of spam email that is particularly annoying or unwanted, often with a green-colored background or theme.
4. Green Energy News: In the context of renewable energy, "Green Mail" might refer to a newsletter or email service that provides updates on green energy news, innovations, and industry developments.

If you could provide more context or clarify which "Green Mail" you're referring to, I'd be happy to help you better!