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1.
an undercover cop/drug deala.

usually is easy to tell if somebody is fettucini because they have something either wikid sick or out of place.
(x): dood check out dem spinnin rims!
(y): dat shit has GOT ta be fettucini, dawg
by d to da g December 22, 2004
 
2.
undercover cop
Yo, that nigga in da Crown Royale gotz to be fettucini, only five-O drive dem thangs.
by Dirty September 18, 2003