Slang of the Week: four fifth (noun phrase)
a .45 caliber gun

Example:
Ed liked to think he was a persuasive speaker, but when dealing with business associates, he found his four fifth was more convincing.

Celebrity quote:
“It's deeper than sipping on liq[uor]s, and puffing on spliffs
You might end up sipping on this chrome four fifth”
—Rapper Kaos on the song Reality Rap

A four fifth sounds like it ought to be 80% of something, but the caliber is actually 45/100 of an inch. To make things more complicated, four fifth is sometimes shortened to fifth. For example, in The Realist, rapper Prodigy explains his philosophy of interpersonal relationships: “I settle things with a heavy metal fifth.”

However, that’s not the only meaning of the word fifth. You can hear witnesses on US crime dramas “taking the fifth” (refusing to testify against themselves in a trial). Even more common for most Americans is the association with alcohol; since we have never really taken to the metric system, hard liquor typically comes in a fifth of a gallon bottle (about ¾ liter).

This can lead to even more confusion, since many rappers have equal interests in inebriants and firearms. However, fifths of alcohol are usually specified. Ludacris says he's "...off the chain/Sipping on a fifth of the golden grain" while MJG raps about "A fifth of Hen[nessey]/Fifth of Gin/A fifth for now/And a fifth for then."

The one thing that doesn't come in a fifth is Colt 45 Malt Liquor, a favored beverage of rappers. Though it shares its name with the classic .45 caliber handgun, it most often appears in songs in a 40 ounce (1.18 liters) bottle.

Bookstore
Take a look in our bookstore for books and DVDs on all kinds of slang! This week’s pick: How to Talk American: A Guide to Our Native Tongues by James Marshall Crotty. From Bible Belt Banter to Vegas Vernacular, from Redneck Rhetoric to New England Niceties, Crotty's savvy and often hilarious region-by-region guide to the way we talk provides a dead-on (and sometimes too strange) indication of how we think, how we behave, and what we hold dear.