Nasal vowel

A nasal vowel is a special vowel sound. It is made when air comes out of both the nose and the mouth together. This happens because the soft palate, a part of the roof of the mouth, lowers to let air escape through the nose.

For example, in French, there are sounds like /ɑ̃/^ⓘ, and in Amoy, there are sounds like [ɛ̃]. These are different from regular vowel sounds. Regular vowel sounds are called oral vowels because no air comes out of the nose.

In many languages, vowels next to letters like “m” or “n” can sound a little nasal. This happens naturally when the mouth changes shape. In English, the vowel in the word hand is affected by the “n” that follows it. But English does not treat nasal and oral vowels as very different.

However, some languages, like French and Portuguese, treat nasal and oral vowels as very different. In these languages, changing a vowel from oral to nasal can change the meaning of a word. For example, in French, beau /bo/ means “beautiful,” while bon /bɔ̃/ means “good.” In Portuguese, mau /ˈmaw/ means “bad,” and mão /ˈmɐ̃w̃/ means “hand.” Even though English uses some French words with nasal vowels, like croissant, English speakers usually do not make the nasal sound as strongly as people in France or Portugal do.

Influence on vowel height

When a sound like "n" or "m" comes before a vowel, it can change how the vowel sounds. This change can make the vowel sound a little higher or lower, depending on the language.

Some languages change high vowels more, like Chamorro, while others change low vowels more, like Thai. Most languages change all vowels this way, but not always in the same way.

Degree of nasalization

Some languages, like Palantla Chinantec, have vowels that sound a little bit nasal and vowels that sound very nasal. People write these differences using special symbols above the vowel letters. One way is to use a tilde symbol, like ⟨ẽ⟩ for a lightly nasal vowel and ⟨ẽ̃⟩ for a heavily nasal vowel. Another way is to combine the tilde with something called an ogonek, like ⟨ẽ⟩ vs ⟨ę̃⟩. The ogonek helps avoid mixing up these symbols with tone marks used in some languages.

Origin

Rodney Sampson explained how nasal vowels came about in modern French in three main steps. In Old French, vowels began to sound nasal because of sounds before them. In Middle French, these nasal sounds became softer. By the time French became what we know today, those special sounds were gone.

Many languages develop nasal vowels when certain sounds change over time. This often happens when sounds at the start of words become simpler.

Orthography

Languages that use the Latin script can show nasal vowels by adding a silent n or m at the end of a word. This happens in French, Portuguese, and Yoruba.

Sometimes, special marks called diacritics are used. In the International Phonetic Alphabet, a tilde (~) is placed above the vowel symbol. Some languages, like Portuguese, also use the tilde. Others, such as Paraguayan Guaraní, use a diaeresis (¨). Some languages use a hook under the letter, called an ogonek, like in Polish. The Pe̍h-ōe-jī system for Taiwanese Hokkien uses a small n above the vowel. In old Icelandic texts, a dot above the vowel shows nasalization.

Languages

Many languages use sounds where air comes out through the nose while making a vowel sound. Some of these languages are French, Portuguese, Japanese, and Bengali. Others include Guaraní, Haitian Creole, Navajo, and Scottish Gaelic. This special way of making sounds is called a nasal vowel.