MJ at rank 1,465 is almost certainly a registry artifact in the most literal sense: initials entered into a licensing form where a full name was expected. Seventy-three records is a small count, and the gender-neutral flag tells you these entries come from owners across different demographics who arrived at the same two letters by different paths.
Multiple Readings, One Entry
MJ can abbreviate Michael Jordan, Mary Jane, or simply be the initials of a beloved family pet's legal name that owners shortened to something more casual. The pet licensing database cannot distinguish between these scenarios. What's consistent is that owners who use initials instead of full names tend to have a casual, affectionate relationship with the naming act — this isn't a considered aesthetic choice so much as a practical one.
The Sports Connection
Michael Jordan remains the most loaded referent for MJ in American culture. A dog named MJ after Jordan is in the same category as pets named Messi or Kobe — athlete tribute names where the initials do the same work as the full name. The difference is that MJ as initials requires some cultural knowledge to decode, which appeals to owners who like a name with a hidden layer.
Is This Really a Pet Name?
Honestly, MJ works as a pet name precisely because it sounds like a nickname already. Two quick syllables, no ambiguity about pronunciation. If you're considering it, the full pet names directory has longer versions like Marjorie if you want something the vet's office can spell correctly on the first try.