Italian racial slur; Only for One Italian to define another Italian. As Black People use the word N*gga.
Guineas and Guidos are NOT the same thing.
People usually say, Guidos are Italian. Not true. Guidos are basically wanna-be Italians. Men that dress like the stereotypical Italian or Italian American just to receive recognition by others. Many people tend to call Italians "Guido". Best bet is to just not call an Italian a Guinea if your NOT Italian, unless you want a pissed of Italian wanting to kick your ass.
An Italian Speaking to Another Italian.
Salvatore : Hey there you damn Guinea. How you holdin' up?
Roberto : Pretty good... You're self?
A Non-Italian Speaking to an Italian.
Bob: Hey ya guinea! Hows it going?
Roberto: Call me a guinea again and I'll push those words out your ass.