look up any word, like blumpkin:
 
2.
Referring to a large area of flab on or around the midsection. From the groin to the chest.

John Lion's mansack pales in comparison to that of an elephant seal.
by Mansack McGee March 03, 2006
 
1.
A dudes balls............
Dude i just racked my mansack on that 12 stair before and then i slid on my face.
by Matt December 15, 2004
 
3.
A term often mistaken for male genitalia. The correct definition of the word is a modern day 'man bag', or the use of a male friend to carry female essentials on a night out/date/general laziness to carry a handbag. Such items include make up and a purse.
Example 1:
Girl: "You're my man bag for tonight";
Guy: "Correction. I am actually your man sack";
Rest of group proceeds to laughter.

Example 2:
Girl 1: "Who is he?";
Girl 2: "I'm not sure, he'd make a good man sack though".
by TheAgeOfAndy July 16, 2010