A long-lasting, most likely goofy looking smile that does not go away for an extended period of time. This most likely happens when surrounded by awesome company, and great music in the middle of the ocean or on a tropical island.

The outward expression of absolute bliss.

The smile caused by compliments or flirting which is difficult to remove from ones face.

PerM A GriN = A state of real, complete, happiness, usually associated with a long lasting smile with blissfully wide post-coital grin. This blank, starry eyed grin is only experienced under rare conditions in the mountains, open freeways, water and occasionally Sky

A state of real, complete, happiness usually only experieced in the mountains.

It's the " permanent grin " you receive when you're stoned.

the 8+ hour long visage of transcendental amusement that accompanies psychedelic experiences, namely LSD and shroom trips.

An automatic and irremovable smile that appears on the face of people who are thoroughly intoxicated with some narcotic; usually marijuana, hashish, mushrooms, or lsd. Can be found in other cases such as on television morning news anchors, beauty pageant contestants, pop queens, and mental patients.