Definition of polyglossy in US English:

polyglossy

noun

Linguistics
  • The coexistence of two or more languages in one area or situation.

Origin

Early 20th century; earliest use found in Journal of Hellenic Studies. From poly- + ancient Greek γλῶσσα tongue + -y. Compare French polyglossie multilingualism.

Pronunciation

polyglossy

/ˈpɒlɪˌɡlɒsi/