A derivitive of the term "big ups"
(noun) origin - Jamaican 1980s. singular and plural.
1. An expression of support or encouragement.
2. An expression of remembrance.
When one person talks about their accomplishment, another person in their discussion chimes in about how they have either already done that or how they have done something else. Common among friend groups, and acquaintances.
"John needs to stop fucking one upping everyone!"
"Stop one upping and let me tell my story."
Dude, if you jump over that piranah plant, over the lava, onto the turtle, bounce off that, land on that tunnel and press 'down' you go in a secret level, there's a one up.