monoglot

/M AH0 N AA1 G L AH0 T/
noun
  1. 1

    A person capable of speaking only a single language.

adjective
  1. 1

    Capable of speaking only a single language; monolingual.

    โ€œHe thought Britain was more monoglot than ever.โ€

Synonyms

Source: https://en.wiktionary.org/wiki/monoglot