Essentially, is any big back activity. Not to be confused with backtivity. Big backtivities are things that contribute to a person forming or maintaining a big back.
"This man ate a whole family meal on his own and then finished off the pie for dessert."
"Man what? That's some big backtivity fasho."
"Man what? That's some big backtivity fasho."
by Marica Linn November 16, 2023
Get the big backtivitymug. by aaaaaayaaaaaa July 16, 2019
Get the Big Gmug. 
The meeting spot of all meeting spots in NUI Galway. Located between the Library and Concourse, no one knows exactly what it is or what it’s there for. But without it, first year arts students would forever roam the campus, lost to time.
by Cagfagbag November 5, 2019
Get the Big yellow thingmug. Very erect penis.
Kenny: Jane Anderson, Do you like my big belt?
Jane: I wanna flex my big belt too, I want it seasoned with some head!
Jane: I wanna flex my big belt too, I want it seasoned with some head!
by PencilBuzz August 17, 2023
Get the Big Beltmug. 
by grace_williams_official July 6, 2020
Get the big fat dogmug.