Hagia Sofia
Is this a specific thing?
Lots of churches are named “Hagia Sofia,” it turns out. The phrase is Greek for “holy wisdom,” which can apply to a lot of things.
The Hagia Sofia is a mosque in Istanbul. It was originally an orthodox church, then a Roman Catholic church, then a museum, and now (very recently) it’s a mosque. When it was built in the 500s, it was the world’s largest interior space.
The disambiguation page for “hagia sofia” lists dozens of churches, both current and historical, that have used the name. In fact, Saint Sofia church in Bulgaria gave the capitol city its name.
Why I Looked It Up
I’ve heard the phrase a number of times in the past, but I can’t remember if they were referring to the general concept, or the Turkish building.
More specifically, I found it in Cloud Cuckoo Land, which was partially set in Constantinople of the 1400s (now Istanbul). In that instance, it was referring to the specific building.