A friend of a Florida neighborhood watch leader who gunned down an unarmed teen last month says that people shouldn't judge his pal for using a racial epithet because in some parts of the U.S., "people proudly call themselves coonasses."

After reviewing a 911 call George Zimmerman made before killing Trayvon Martin, many believe they hear the shooter calling the 17-year-old a “fucking coon.”

On Monday, MSNBC host Chris Matthews asked longtime Zimmerman friend Joe Oliver if he was surprised that he would have used this kind of language.

"To me, it's a matter of interpretation of whether he saying 'coon' or 'goon,'" Oliver replied. "There are a lot of parts of this country where people proudly call themselves coonasses. In Louisiana, in particular."

According to Dictionary.com, "coonass" is a vulgar, disparaging, and offensive offensive term sometimes used to describe Cajuns in Louisiana and Southeast Texas. It is thought to come from the French word "connasse," a vulgar term for a woman, similar to whore, bitch or cunt.

While some Cajuns do use the word with pride, it is always considered to be a racial slur when directed at a black person in any other part of the country.

Oliver continued: "On the other hand, you know, I'm a 53-year-old man and I don't know too many people younger than 40 who use that term as a racial slur. As far as the other word, 'goon,' I've been informed by my 17-year-old daughter that that among her peers is a term of endearment."

In an interview on ABC on Sunday, Oliver had first suggested that Zimmerman had used a "term of endearment" before killing Martin.

Authorities told the Orlando Sentinel on Monday that Martin had been the aggressor even though Zimmerman was heard on the 911 calls saying he had been pursuing the teen.

Zimmerman said he was walking toward his SUV on February 26 when Martin approached him from behind and attacked him after the two exchanged words. Zimmerman reportedly claimed to police that he shot Martin in self-defense.

Witnesses have apparently corroborated some of Zimmerman's story, but no one has come forward to say they saw the initial punch, according to the Sentinel.

Martin’s parents and lawyer have said that Zimmerman, who is still free, should be arrested for pursing Martin despite 911 dispatchers urging him not too.

Watch this video from MSNBC's Hardball, broadcast March 26, 2012.

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-- with earlier reporting by Andrew Jones