Of course it is.

Although it doesn't list in the Oxford English dictionary, its derivation is from the bastardisation of a regular noun, and it is in effect a slang term, it still qualifies due to the de facto nature of it being recognisable in modern usage.

A quick google would show it listed in Merriam Webster, which should we be being pedantic, is plenty enough to justify its qualification, even in this country.

As Connery once said, "Here endeth the lesson".