First introduced by Smith&Wesson in 1990. Ballisticly similar to the 9mm parabellum, but with muzzle velocity exceeding all 9mm loads, and exceeding most standard loads of the outdated .45ACP cartridge, while having a standard magazine capacity of as many as 15 rounds (G22) as compared to the 7 round standard 1911 magazines, or the awkward-to-hold 13rd G20. Despite the belief or most inexperienced with the round, the .40 S&W has noticeably more recoil then the .45ACP.
Ironically, Austrian manufacturer Glock beat Smith & Wesson to the dealer shelves in 1990, with pistols chambered in .40 cal.
by hassell August 16, 2007
Get the .40 cal mug.
A .40 cal is not a big fucking gun, it's an improved version of the 9mm. What it really is is a 10mm bullet, and packs more punch than the 9mm, but still allows for the same (high capacity) amount of rounds to be held in a clip. A favorite of drug dealers.
"Still tote a glock .40 for the haters and the bustas" -T.I "A.S.A.P"
by GetYoWeightUp July 1, 2005
Get the .40 cal mug.
A .40 cal is an improved version of of the 9mm. It is about the same size but packs more power, a favorite of drug dealers.
"Still tote a Glock .40 for the hatas and the bustas" -T.I. "ASAP"
by GetYoWeightUp June 28, 2005
Get the .40 cal mug.
A caliber developed by Smith & Wesson for women and limp-wristed men, this cartridge is slightly more powerful than the 9mm but does not approach .45 ACP
That punk pulled a .40 cal on me! I took out my 1911 and blew his fucking brains out!
by ein klein November 4, 2006
Get the .40 cal mug.
.40 Cal: Simply put, a big ass fucking gun. Usually a semi-automatic with no safety and a rubber grip handle. It will fuck you up.
".38? Fuck a Saturday Special. I'm rollin wit da .40 cal. Let's see a nigga try n get buck round me."
by Dr. F. Roy Dean Schlippe April 18, 2005
Get the .40 cal mug.
0.40 calibur ammunition, Smith and Wesson, is a calibur of bullet becoming increasingly used by gun manufacturers. It was originally designed to have the stoping power of a 0.45cal ammo, with the smaller size of 9mm. The FBI held a series of tests looking for a new ammunition after it decided the 9mm did not have enough force for it's agents to quickly neutralize a target. It decided on the 10mm, which is a somewhat rare load, with only a few pistol makers such as Glock making pistols which utilize it. The FBI eventually settled on the 0.40cal, Glock 23, as standard issue for it's agents. The new round was more powerfull than 9mm, but was similar enough in size that the size and shape of a pistol can be the same as that of a 9mm and it can still hold sufficient rounds.

Many times a person refering to a 40 cal is actually talking about the gun which uses this ammunition, rather than the ammo itself.
Akon- "I keep the 40 cal on my side."
by docmo October 4, 2006
Get the 40 cal mug.
An illegal gun

A Dipset Rapper
Man 1 : "I Just Bought a 40 Cal for $50".

Man 2 : "How the hell you buy a rapper"?

Man 1: "No the gun you dumbass"!
by hToWnBaLLa21 May 26, 2006
Get the 40 CAL mug.