Sup
Stand up paddle board
Sup means "Stand up paddle board," which is a larger variation of a surfboard where the rider stands up on the board and navigates the water using a paddle. The abbreviation may be used as a noun to refer to a single board or as a verb to refer to the activity of paddle boarding.
There are many different forms of stand up paddle boarding that have been documented around the world, including African coastal countries and Hawaii. Paddle boards may be used for fishing, yoga, racing and wave riding competitions, transportation, or just for hanging out on the water. While sup has been popular among coastal inhabitants for years, its popularity didn't spread to non-coastal locations until the 2000s. Sup is now a common sight on lakes and rivers as an alternative to kayaks and canoes.
Example
Baseball Slang Quiz: Can you bat 1.000?
Kewl kids use sup as shorthand for "What's up?" This abbreviation is a quick way to ask "How's it going?" and/or "What are you doing?"
Sup is more casual than "What's up?," so you should likely use it only among friends and family. You most certainly should not use sup while talking to someone you want to impress, such as a potential date on an online dating app.