Waking someone up by ejaculating on their face.
Did you hear about the guy suing the YMCA? He was taking a nap and some dude gave him a Boston Alarm Clock.
by JPeterson December 18, 2013
When you pull your pants down, straddle a bum's face, and fart on it to wake him up.
I just gave that hobo that sleeps outside of Tony's Pizzeria the old Boston alarm clock.
by Runer112 October 16, 2010