A commonly mistaken term. A millennial is a person who is born in the year 2000 or above. This is why they are called millennials; because the year 2000 was the "new millenium".
Millennial: "I was born in 2001."
Non-millennial: "I was born in 1989."
Millennials are people born during this current Millennium, if you're older than that, you're not a millennial. As of the 31st of December 2017 every single person that is not a millennial is over 18, therefore should know better.
"Whats the point in meeting up if you're not going to speak? Millennials are so antisocial, all they ever do is look at their smartphones."
Someone who cannot eat pizza without glorious amounts of Ranch Dressing.
Cashier: Welcome to pizza palace what would you like.
Millennial: I would like some ranch dressing and a buffalo mac'n cheese pizza (or any other millennial pizza that should not exist).
Cashier: The ranch is an extra charge is that okay?
Millennial: Yeah, my parents just put money in my bank account.
Derogatory term for people in their twenties obsessed with avocados, tumblr, pinterest, and awful memes (from tumblr, usually). They also like Friends, and probably do Buzzfeed quizzes. BEWARE!