Isn't the issue mentioned in the pilot? Bashir talks excitedly about "frontier medicine" and Kira snarks that for her it's home.
The Federation had hundreds of ships and stations so would have needed a system of designations, but for Bajor it was the only one so they might not have even needed to give it a name.
The Federation had hundreds of ships and stations so would have needed a system of designations, but for Bajor it was the only one so they might not have even needed to give it a name.