It's a blowjob, but not just any typical blowjob. The main difference is that the blowjob is given by two people instead of just one. The two people acts like the two slices of bread while the reciever's cock is like the meat sandwiched between the two slices of bread. Thus, the name "cockmeat sandwich" and always involve at least 3 people.

From 2008 movie
Harold & Kumar Escape from Guantanamo Bay.

This term was used when Big Bob (a guard in Guantanamo Bay) asked Harold & Kumar to get hungry real fast and eat his cockmeat sandwich with extra mayo.
by lenkun July 16, 2008
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-big bob pulls down pants-
big bob:ready for your cockmeat sandwich?
kumar:i've never sucked a dick before.i bet it sucks dick!
by harold and kumar May 3, 2008
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a complementary snack usually offered by prison guards to inmates. this sandwich consists of a penis, two slices of brown wholemeal bread, and one leaf of lettuce, kindly prepared by the prison's guards themselves. if your lucky you could find extra mayo in your sandwich.
"ready for your cockmeat sandwich... i hope you like extra mayo!"
by paul the mighty egg layer March 12, 2009
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A blowjob performed by dirty stupid terrorists that stink like two cunts

where two dirty taliban mother fuckers act as two slices of bread on either side of the cock. therefore making a dirty sandnigger cockmeat stinking sandwich
hey man i just got a dirty cockmeat sandwich from Osama and saddam fuck they stink like ass
by alex_555666777888999 September 26, 2008
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When a man named Lamar from the Bay Area puts his penis in a marinaid or sauce that is then used to flavor any type of meat. The resulting dish is extremely delicious and irrestable. It can not be recreated by anyone other than Lamar himself.

It doesn't have to be a sandwich.
Yeaaaah, I want some of that cockmeat sandwich, it's helllllla gooood.
by Yadidameng December 26, 2011
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someone that negatively comments everything and thinks he's the ish
Really Bob, you`re such a cockmeat sandwich.
by ashmendd January 8, 2009
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