Short beard stubble on a man's face that has grown since the morning shave, usually experienced towards the end of the day.
Can be used to describe a man who looks scruffy, overworked/tired, hung-over or rugged.

"Rough night last night? Got that 5 o'clock shadow."
by StephenCarr October 18, 2005
the facial hair that comes late in the day when a man has shaved earlier
Naturally he had a 5 o'clock shadow again.
by The Return of Light Joker April 17, 2008
When you purposely walk in on your brother jerking off while your jerking off.
"I had that Paris Hilton video going in my room while I was cranking one out, when my older brother bill-dog walked in on me while he was beating off and laughing like a maniac! Bill-dog hit me with the worst 5 o'clock shadow! I was so embarrassed!"
by normal dude September 12, 2009
An abundance of pubic hairs that have collected on the rim or bowl of a toilet or urinal.
Yo! Someone needs to shave the pisser man, its got a nasty 5 o'clock shadow.
by nate_j_y December 7, 2005
When one develops an orange stain around the lower face after a day of sitting on the couch and eating Cheetos.

The mark of a true couch potato.
Girl 1: I come home from work every day and my orange-faced boyfriend is just sitting there with the remote.

Girl 2: Uh oh, its a 5 o'clock cheesy shadow.
by TheMusicNote18 March 9, 2011