Meaning
A full-body black cat, built by joining the cat emoji with a black square. It shows the animal in solid black, the colour linked to old superstitions and to witches in folklore.
It appears in Halloween posts with 🎃, spooky aesthetics, black-cat-owner pride and jokes about bad luck, though many owners use it to say the opposite. Example: “Adoption day! Black cats are the sweetest, ignore the superstitions 🐈⬛”.