A "dick-off" is a challenge between men to see who's penis is longer...
Billy: I bet mine is bigger than yours!
Tom: No way man, there is no way yours is bigger than mine.
Billy: Well I guess we will have to have a "dick-off"
A competition between guys to see who has the biggest dick.
Person 1 : I bet my shlong is far bigger than yours
Person 2 : Theres only 1 way to find out, lets have a dick-off
A special competition between two males that often occurs AFTER heavy consumption of alcohol in which each adorned contestant needs to prove his superior masculinity over his rival. Often times, this will take place during an afterset (a party that occurs at someone's residence after an alcohol-serving establishment has closed for the evening). In order to crown the winner of the competition, each contestant must lay his erect penis down on a table and measure the exact length and exact width of the male organ. An appointed judge with no bias towards either contestant must then multiply the measurements (Length x Width) of each contestant and calculate the final statistic. The winner is determined by comparing the final statistic in a "greater-than/less-than" assessment.
For example: Contestant #1 dimensions are 6.75" in length and 2.75" in width, equaling a score of 18.5625. Contestant #2 dimensions are 5.75" in length and 3.25" in width, equaling a score of 18.6875. Therefore, since 18.5625 < 18.6875, Contestant #2 gets to claim the fame of superiority.
Jerome: "Kevin and Dan each think that they're packing more pud than the other."
Giorgio: "Why the heck does it even matter?"
Jerome: "I don't know. I think that they're gonna have a dick-off in front of the ladies at the afterset in order to crown who is king, once and for all."