|place = region|
|Used both as a broad tag for geographic or historical areas with no clear boundary and for distinct administration areas (with specific boundaries) in some countries.|
|Used on these elements|
|Status: in use|
|Tools for this tag|
This is a tag from the earliest days of OpenStreetMap, is used in various way, was never clearly defined and is rarely used by data consumers.
It was used to describe an area with no specific political signification linked to admin_level, but it is part of an area with admin_level=6: https://www.openstreetmap.org/browse/way/74607493
It was used for The Triangle and The Triad, both of which encompass multiple cities and have ambiguous boundaries, because no other place=* seemed appropriate. Rendering based on population=* would probably seem reasonable to the author who is not sure how many non-locals would recognize the names.
In Czech Republic it is used to mark = NUTS 3 (Region) which is admin_level=6