A person with two languages is bilingual. A person with three or more is multilingual. Looking for a word that describes the exact number of languages would seem disingenuous.
You would be "quadrilingual."
people who can speak 4 or more languages are commonly called, multilingual.
A person who speak different languages is called a Linguist.
Being able to speak two languages is called bilingualism.
A person who can speak two languages is called a bilingual.
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Someone who can speak two languages is called bilingual.
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multilinguist, polyglot; use dictionary.com for more reference
A "polyglot" is someone who knows several languages.
Multilingualism.
Bilingual bi ( two) lingi or lingu ( tounge) so two languages