look up any word, like porb:
 
1.
1. In a wedding party, the next ranking groomsman after the best man. Often the X-factor at the bachelor party, and wedding reception responsible for turning things up a notch.

2. On a gang or team, the third ranking member. Often a wild card or tough guy.
"After winning and then losing 3 grand at the blackjack tables, I brought a couple strippers back to the bachelor party suite, and finished them both off. Just another night glorious night as a left hand man."

Historical examples: Mr. T in The A-Team, Zach Galifianakis in The Hangover, Dennis Rodman on the Chicago Bulls, Raphael from 'Teenage Mutant Ninja Turtles', Will Ferrel in 'Old School', Booger in 'Revenge of the Nerds',
by Buster Chestnutz March 27, 2010
 
2.
A guy who will cockblock an entire friendship group of males from impressing a female by making some stupid comment, so she looses respect for the other males as she thinks their all going to be like that.
All the guys thought hey this girl is good fun we've got banter.

The left hand man started to meticulously pick apart all the random sweeping statements, turning the event into a boring moan at the female not giving enough facts in the pub on a friday night!
by Sazzy Jo March 30, 2014
 
3.
A righthandman for a left hander
I'm lefthanded so I have a lefthandman instead of a righthandman.
by UJ the boss January 05, 2012
 
4.
The lowest ranking male in a gang bang with 3 or more guys and only one woman.
"Ron Jeremy wasn't always the king of the porn world. Rumor has it he was originally the left hand man in a few John Holmes movies (citation needed)."
by buster chestnutz March 29, 2010