The name is likely a remnant of an old linguistic database.

Are you interested in the in Germany? IPA Pronunciation Guide - Vocabulary.com

The International Phonetic Alphabet (IPA) is a phonetic notation system that is used to show how different words are pronounced. Vocabulary.com The Production of Speech Corpora

: The structural tagging (likely XML) that allows a computer to distinguish between a "Street Name" and a "Surname."

: Millions of entries had to be converted from physical paper to digital text.

: The data had to be "tagged"—a process known as markup —to separate the name, the address, and the phonetic pronunciation. The Secret "IPA" File

Do you need help from a specific markup file?