Jungseong

Jungseong is the term for the vowel component of Hangul, the Korean alphabet. In a standard Hangul syllable block, the structure typically includes an initial consonant (choseong), a medial vowel (jungseong), and an optional final consonant (jongseong). The jungseong determines the syllable’s vowel sound and interacts with the other components to yield the pronunciation.

In the modern Korean system, there are 21 jungseong: 14 simple vowels and 7 complex vowels formed by combining basic vowels. The simple vowels are ㅏ, ㅐ, ㅑ, ㅒ, ㅓ, ㅔ, ㅕ, ㅖ, ㅗ, ㅛ, ㅜ, ㅠ, ㅡ, and ㅣ. The compound vowels are ㅘ, ㅙ, ㅚ, ㅝ, ㅞ, ㅟ, and ㅢ. These vowels correspond to sounds such as a, ae, ya, yae, eo, e, yeo, ye, o, yo, u, yu, eu, i, with the compound vowels representing combinations such as wa, wae, oe, wo, we, wi, and ui.

Historically, Hangul was created in the 15th century by King Sejong the Great and scholars of the Hall of Worthies to provide a phonetic script for Korean. The vowels were designed to be distinct and easy to write, and the system’s Jungseong are used both as standalone letters and as the medial element within syllable blocks.

In contemporary use, Jungseong appear in every Hangul syllable and are represented in Unicode as individual jamo or as parts of precomposed syllables. See also Hangul, Jamo, Choseong, Jongseong.