An eightball consumed before going to bed by someone who has the ability to go to bed after an eightball. If said person does not have the tolerance to go to sleep, the consumption does not constitute a nightball.
by Jewbacchus August 4, 2007
A slimy ball that randomly appears in your dryer after you leave it on over night, some northern cultures eat it as delicacy. A night ball is mostly made of mucus that is collected in the anal cavities and then transferred to ones under bridges and then the dryer
"Hey kate, can I use your phone as a light so I can find an outlet?"
"No i'm using it"
"DON'T BE SUCH A NIGHTBALL"
"No i'm using it"
"DON'T BE SUCH A NIGHTBALL"
by johannavannippleballs November 24, 2011