look up any word, like bukkake:
 
1.
Similar to a low five between two bros, but with the added flair of a sixth digit, aka one's dick.

Commonly performed on nude beaches, this is seen as the ultimate gesture of friendship.
"dude bro i was giving this guy a low five but he was so clutch that it became a low six"
by Sirblondie December 07, 2008