Language interpreting or interpretation is the intellectual activity of facilitating oral and sign-language communication, either simultaneously or consecutively, between two, or among three or more, speakers who neither speak nor sign the same source...

Language education

Polyglot, a person skilled in multiple languages

The Linguist List, online linguistics resource

Chartered Institute of Linguists

A specialist in languages, including translators, interpreters, and language teachers.

A specialist in linguistics. See List of linguists for prominent linguists in this sense.