The close-mid back rounded vowel is a type of vowel sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is o, and the equivalent X-SAMPA symbol is o.

Features of this vowel:

• Its vowel height is close-mid, which means the tongue is positioned halfway between close vowel and a mid vowel.
• Its vowel backness is back, which means the tongue is positioned as far back as possible in the mouth in the mouth without creating a constriction that would be classified as a consonant.
• Its vowel roundedness is rounded, which means that the lips are rounded.

Occurs in:

• French réseau [ʀeˈzo] 'net'
• German Kohl [koːl] 'cabbage'
• Spanish todo [ˈtoðo] 'everything'

In many English dialects (e.g. General American), this vowel occurs as the first part of the diphthong [oʊ], as in hope [ˈhoʊp], go [goʊ].