Very tight, upper-thigh length shorts that were popular in the 1980's and were a staple of Tom Selleck's wardrobe in the popular television series Magnum P.I.  These shorts usually clearly outline one's package and leave nothing to the imagination.  Frequently worn by those with a mullet.
I was out of clean clothes so I threw on some Magnum PI's. I spent all day tucking back the meat to keep from playin turtle and scaring the locals.
by Salvadore McGillicutty June 16, 2008
 Get the Magnum PI'smug.
Get the Magnum PI'smug. by TrashPanda81 February 16, 2022
 Get the Magnum PImug.
Get the Magnum PImug.