Lingual means relating to the tongue or to language.

In medical or dental settings, lingual describes things connected to your tongue. A dentist might examine the lingual surface of your teeth (the side facing your tongue), or a doctor might look at your lingual nerve, which helps your tongue sense taste and touch.

More commonly, you'll encounter lingual in words about language. When someone is bilingual, they speak two languages fluently. A multilingual person speaks several languages, while someone who's monolingual speaks just one. These words all share that root meaning of “tongue” because we use our tongues to form the sounds of speech.

The connection between tongue and language makes sense: your tongue is essential for speaking. When you learn a new language, you're training your tongue to make new sounds and teaching your brain to think in new patterns.