Excessive talking, sometimes to the point where it gets
boring and drags on for way too long, aka rambling.
It's a
slang word used in Britain, but mainly in London or other parts of
England by roadmen / younger generations.
"Bro my Psychology
teacher is so boring, they're always waffling about nonsense that has nothing to do with the lesson."
"I definitely failed that History
test, I just waffled tbh."
"That Biology question was so long and irrelevant, there was so much
waffle in it I barely knew what they were asking me to do."