While crouched over your partner and receiving a hummer you defecate on your partner's neck, hence a brown bow-tie. Note that the person delivering the brown bow-tie must be facing his partner's head, lest he deliver a brown sombrero.
"While Sarah was giving me a hummer last night, those refried beans kicked in and I couldn't help but give her a brown bow-tie!"
rewinding an on-demand or DVR-r'd program, to watch it again, because you weren't paying attention the first time.
I'm watching Entourage, and Brad was smoking pot and laughing about something stupid when Turtle told Tom Brady to suck balls. Brad decided to 'brown the runway' and re-winded Entourage and I had to watch it again because he's an idiot.
Brown Cloud: Truely, a fart is a release of tiny poo particals into the air. Magnified, the particals create a, "brown cloud". So the next time you walk into a fart, remember to keep your mouth closed- otherwise you are injesting poo particals AKA brown cloud.
Next time you fart in a crowd, look around at those who are injesting last nights dinner, and celebrate silently.
"Hey dude, I just farted and everyone around me is standing in my brown cloud."
"My brown cloud has taste of last night's fried chicken!"