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2.
203
M16 rifle with 40mm grenade launcher attached.
"The 203 is a soldier's best freiend."
by Diego July 29, 2003
 
1.
203
The state of Connecticut area code
Woodbridge, CT is located in the 203 area code
by BMoney January 27, 2005
 
3.
203
M203

The 40mm projectile launcher that can be mounted to the bottom of a rifle. Commonly seen as a grenade launcher on M16/M4 style military weapons, and has its own stand-alone trigger/hammer.
Jimmy Joe just nailed that Iraqi van with his 203.
by M4ownsYou January 17, 2006
 
4.
203
The m-16 carbine with grenade launcher attachment Scarface uses in his movies, also an "urban solja"'s weapon. This is why all those rappers have scarface playing in their house.
Say hello to mah lil' friend!
by Konduct April 08, 2004
 
5.
203
Your friend and sometimes your worst nightmare in the game "America's Army" The 40mm grenade launcher mounted under the popular M16.
HAHA! That stupid arab newb got pegged by my 203!
by Doraemon1210 April 25, 2005
 
6.
203
M16 rifle with 40mm grenade launcher attatched. used by the sas. i dont know if its used by other reginements or counntrys.
i stuck a new mag in my 203.
by moggybiter May 04, 2009