1. the quality or state of having many names or being known by multiple names
Usage: formal; linguistics and onomastics
2. in linguistics, the phenomenon in which a single entity or concept is referred to by different names across languages or dialects
Usage: technical; comparative linguistics

Examples

• The polyonymy of the city is evident in its various historical names: Constantinople, Istanbul, and Byzantium.
• Scholars studying polyonymy discovered that the same plant species had dozens of regional names across Europe.
• The polyonymy of the mountain reflected the different cultures that inhabited the surrounding regions.
• Understanding polyonymy helps linguists trace cultural contact and historical migrations.
• The author's polyonymy—publishing under multiple pen names—made it difficult for readers to recognize her body of work.