If you're planning to end up in prison soon, you might want to brush up on your lingo before the judge bangs his gavel: As a new boot you'll need to watch out for showerhawks, 5-Os, and snitches. And the last thing you'll want to order in the cafeteria is a tossed salad.

Thankfully, there's A Prisoner's Dictionary, a site created in 1995 by Arnold Erickson as part of Prisonwall.org, a mega-site aimed at showing the reality of life on the inside.

At this online dictionary, users can browse through hundreds of words and definitions, from oft-used terms such as homeboy (a friend or another prisoner from one's hometown or neighborhood) or crib (home on the street) that have filtered down into the vernacular to more obscure patois such as kitestringing (messages or bags of property sent from cell to cell via homemade string) and Dragon's Tongue (sliced corned beef from the cafeteria, boiled to an unexcelled toughness.

But the site isn't really meant as a primer for budding convicts, Erickson said. It's intended to reflect the reality of life behind bars during a time when many important decisions about prisons in the U.S. are being pondered.

"You wouldn't want to go in with a list of these terms and expect to know what's going on," he said. "But people on the outside need to know what the prison experience is and what it does, and these words reflect the [prisoners'] experience, they deal with things that are important to them."

The terms in Erickson's list cover virtually every aspect of a prisoner's life — from food to clothing to drugs, and even sex. It's no surprise that many of the terms deal with the biggest issue facing inmates — the length of his or her sentence.

A prisoner serving all day and a night, for example, has life without parole whereas a prisoner serving a deuce has a date, or release date, of only two years.

And for those on Buck Rogers Time, according to the dictionary, their parole date is so far into the next century the inmate cannot imagine release.

The site, which now gets about 10,000 hits per month, wasn't always so comprehensive. Erickson launched it in 1995 with about 50 words he had collected from his experiences helping prisoners as part of a non-profit group in California (he now works on capital appeals as a deputy public defender for the State of California).

But since then, thanks to his own work and the contributions of people from around the country, the site has burgeoned.

A Prisoner's Dictionary now offers definitions to hundreds of prison terms, some specific to certain regions or even certain prisons. And meanings can vary subtly from state to state: Whereas the term "bitch up" means to chicken out or to be a coward in Texas, it means to cry or to give in in New York.

Erickson is not the first to shine a spotlight on prison vernacular, said Laurence Horn, professor of linguistics at Yale University.

"Criminal argot has been studied for hundreds of years as not only a very interesting form of language in its own right but also as a way that the larger language is infused with new words and new meanings for old words," Horn said.

Erickson's also not the only one with an online dictionary.

His site is a prisoner-oriented guide, but others have taken a different focus. The Correctional Officers Guide to prison lingo is focused on helping law enforcement professionals break through the prison patois, while a site run by the British government is aimed at helping both prisoners and their families.

There's so much to understand, Horn explained, because prisons, like other subcultures, are specialized societies that develop their own natural twist on the language used outside.

"As in any situation in which there's someone who doesn't have a whole lot of power but has a lot to express," Horn said, "an in-group develops terms that are opaque to outsiders that enable it to communicate without the message being interpreted."

But it's not long before terms seep into the mainstream, Horn added. "[These vernaculars] have a sort of covert prestige because they involve this macho image that young men might seek to emulate," he said.

One quick look at MTV, he said, and that much is obvious.

But while Erickson agreed that his site could serve as a music video decoder or even give avid HBO fans an inside track to the network's hit prison drama, "Oz," he said the site has helped more than just the casual or curious user.

Families of prisoners, former prisoners, correctional officers, and even prisoners themselves have written in with new words and messages of support for the site.

It's this sentiment that drives the lawyer to continue A Prisoner's Dictionary and its parent site, Prisonwall.org, a commitment he maintains on a solely volunteer basis.

"When a person is placed behind a prison wall, they are not only separated from society. Society is separated from them," Erickson said. "There are forms of expression that can never be fully understood by the outside world. As a result, this list will never be complete."

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