This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

adj. of, or relating to a toponym

adj. named after a place

Pertaining to toponymy: as, toponymic terminology.

"This immediately smells like false parsing to me since one could equally come up with other ad hoc 'toponymic formants' like *-asia and find examples like Ocrasia and Planasia to serve as 'evidence' with far too much ease to suit my skeptical nature."