What are Long Vowels in Japanese? 長音 chouon

Quick! What's the difference between these two words?

Calling a middle-aged lady, 「おばあさん」 will most likely be seen as an insult.

Calling an older, grandmotherly lady, 「おばさん」 will most likely be seen as a compliment.*

* It's best not to do either until you know the lady and she invites you to call her 「おばあさん」 or 「おばさん」 .

長音 Long Vowels

Many Japanese words have long vowels. This is called:

長音(ちょうおん)

chou on

The word, 長音(ちょうおん), itself has a 長音(ちょうおん) sound. (Sorry, couldn't resist.) The う u sound makes the ちょ long.

• The long vowels do not add syllables: ちょ and ちょう are both one syllable.
• But with Japanese, it is better to think in terms of "mora" instead of syllables. 

A mora basically represents a single kana. The kana with a small やゆよ and the small っ count as one mora. You can think of it as lasting one beat.

For example, 東京(とうきょう) (Tokyo) is two syllables (Tou / kyou) but four mora: と - う - きょ - う. So, it lasts four beats.

Likewise, 長音(ちょうおん) is two syllables but four mora. It is pronounced as four beats: ちょ - う - お - ん.

Thinking in terms of beats (one beat for each mora (or kana)) will greatly help your Japanese pronunciation.

• As a result, the vowel sound, usually, will sound the same, just held longer.
• The long vowels are about twice as long as a short vowel. (Two beats instead of one.)

Rules for making longer sounds with Hiragana

For the most part, the following makes sense. The same vowel sound is pronounced twice as long and written with the hiragana that that sound represents. The last two, え and お, have a variation in the written form, however.

• For sounds ending in an あ a sound, add an あ:
  おばさん (aunt) → おばあさん (grandmother)

• For sounds ending in an い i sound, add an い after it:
  おじさん (uncle) → おじいさん (grandfather)

• For sounds ending in a う u sound, add an う:
  くこ (Chinese wolfberry 枸杞) → くうこう (airport 空港)

• For sounds ending in a え e sound, add either an え or い. While this can be confusing, just memorize which one as you learn vocabulary words.
  おねえさん (older sister; young lady お姉さん)
  へいき (calmness 平気 -or- military arms and weapons 兵器)

• For sounds ending in a お o sound, add either an お or an う. As with the え sound, you will just have to memorize these words. However, most of them use う.
  おき (open sea; okinawa 沖) → おおきい (big 大きい; notice this has two long vowels. お for the お sound and い for the き sound)
  とき (time 時) → とうき (porcelain; china 陶器)

Rules for making longer sounds with Katakana

This is much easier than hiragana. Instead of adding another vowel, simply add a dash after it. ー

コーヒー coffee

アパート apartment

バター butter

Further Practice: Click here for another article on the difference between きて, きって, and きいて.