What is a "condominium development"?

Question

The Canadian census has this

"Is this dwelling part of a condominium development?"

I do not understand. I understand the word "condominium" -- my apartment is one, after all, and so are the other 54 condos in the building. The building was built ~50 years ago, converted from rental to condo ~30 years ago. What sort of development is this talking about? It really doesn't help my occupation is a software developer. As far as I know, development is a change of state from say a less advanced to a more advanced state. Usually when I read about real estate developers, they are building a number of buildings. But you can't live in one if it's being developed because, well, it's being developed aka in the process of being built. I am very confused here.

The official explanation couldn't be less helpful if it tried:

Select “Yes” if the dwelling is part of a condominium development. Include as condominiums those dwellings that are in the process of becoming registered condominiums.

Select “No” if the dwelling is not part of a condominium development.

Answer 1

The word development has this sense in real estate:

American Heritage Dictionary development

3. A group of dwellings built by the same contractor: bought a condo in a new development built by the river.

The group of dwellings is still called a development even after all the houses are built and sold. The official explanation you cited

Include as condominiums those dwellings that are in the process of becoming registered condominiums.

makes it clear that the meaning of development extends to conversions as well as to original construction.