Black as a standalone pet name is almost certainly a paperwork artifact: the kind of name written on a licensing form by someone who described their pet's color instead of providing a name, and the system logged it as a name. That said, as a deliberate choice, it has a specific minimalist appeal worth acknowledging.
A Data Artifact First
Pet licensing databases across cities consistently show descriptor words showing up as names: Black, White, Brown, Big, Small. These entries reflect the friction of mandatory registration; some owners, when forced to provide a name, wrote the most literal description available. The 124 recorded instances of Black in this dataset almost certainly include a high proportion of these form-filling moments rather than deliberate naming choices.
The Deliberate Minimalist Case
For the rare owner who genuinely chooses Black as a name (fully intentionally, for a black cat or dog) there's something to it. It's a color name that dispensed with any ornamentation, the anti-Sable. It has a one-word severity that suits a sleek, self-contained animal. A black cat named Black has a certain dry wit to it.
The Practical Reality
Black is hard to use as a call name; it blurs with other sounds and doesn't project well as a single syllable with no memorable consonant cluster. Compare with Shadow or Midnight, which carry the same dark-coat acknowledgment with far more nameability. Browse all pet names for better alternatives if you're going the color route.