Using the phrase ‘to call a spade a spade ‘ in common conversation is not offensive. It simply means ‘tell it like it is’
To refer to a black person as a spade (a la 1970s American films) is offensive.
3Girls happened to use the phrase in a context which made it look like a racist joke
I came on to say exactly this too. I'm amazed that people didn't get this. The 'joke' is in the double meaning of the word spade, it can be innocent as in the phrase, or it can be racist, and the joke 'works' because its being used to mean both at the same time.
I hope my quotes above convey that I think this is not at all funny and is highly offensive and racist. And it is clear to me the poster did not realise the double meaning so wasn't being deliberately offensive. The phrase is still fine to use, although worth being careful of the circumstances.
A similar type of joke would be the difference between a smoker saying in a normal voice 'I really fancy a fag' to clearly mean a cigarette vs someone saying in a camp voice as a gay man walks past 'I bet he fancies a fag' with an eyebrow wiggle.
Context is everything. And yes a smoker can still describe a cigarette as a fag, and a gardener can still dig with a spade.
I do wonder about quite how dim people are sometimes. Or rather how keen to pretend to not understand simple language concepts and how not to be an offensive prick. Then blame people calling out prejudice for being permanently offended.
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