Young Thug needs to brush up on his definition of snitching, because what Kid Cudi did with Diddy does not make him a rat … at least according to Touré.

The music journalist joined us on “TMZ Live” Friday and we asked him about Young Thug labeling Cudi a “rat” for testifying against Diddy in court.

Touré says Young Thug’s got it twisted when it comes to what is and isn’t snitching … and he schools us too.

Kid Cudi took the stand Thursday and testified Diddy broke into his house after finding out he was dating Cassie … but as Touré points out here, Cudi only called police after directly confronting Diddy. He says that’s what the street code calls for.

Cudi also told jurors he suspected Diddy orchestrated an attack on his Porsche … describing an incident where a Molotov cocktail was dropped inside, burning up his red interior and making the sports car unsalvageable.

Touré says Kid Cudi went about this the right way … and he’s got some strong words for Thug.