Genetic studies have shown that the closest relatives of raccoons are the ring-tailed cats and cacomistles of genus Bassariscus,[2][3][4] from which they diverged about 10 million years ago.

Although there is some variation depending on species, raccoons range from 20–40 inches (51–102 cm) in length (including the tail) and weigh between 10 and 35 lb (4.5 and 15.9 kg).

Procyon brachyurus Wiegmann, 1837 was described from captive specimens; its identity is undeterminable as the remains of the two animals assigned to this taxon cannot be located and may have been lost.

Spanish-speaking colonists similarly adopted their term, mapache, from mapachtli the Nahuatl word for the animal, meaning roughly "that which has hands".

In many languages, the raccoon is named for its characteristic dousing behavior in conjunction with that language's term for "bear": Waschbär in German, mosómedve in Hungarian, vaskebjørn in Danish and Norwegian, tvättbjörn in Swedish, wasbeer in Dutch, pesukaru in Estonian and pesukarhu in Finnish, araiguma (アライグマ) in Japanese, orsetto lavatore in Italian, huànxióng (浣熊) in Chinese and mieshta mechka (миеща мечка) in Bulgarian all mean "washing bear".