An interpreter is a person who translates speech in different languages, usually at conferences or other meetings. There was a movie called The Interpreter. Also, an interpreter is someone who will translate and communicate with people who find normal speech difficult.
Interpreting booths in the European Parliament where interpreters simultaneously interpret debates between the 24 official languages of the European Union (in comparison, the United Nations have six official languages). The European Parliament is the most multilingual parliament and the biggest employer of interpreters in the world.
Two sign language interpreters working for a school.
Interpreter Facts for Kids. Kiddle Encyclopedia.