Combining Inverted Double Arch Above

It signals lip rounding on the base sound.

In the International Phonetic Alphabet (IPA), a notation system for speech sounds, this combining diacritic marks labialization. It modifies the sound shown by its base letter rather than naming a sound on its own. The above form is paired with ◌̫, which places the inverted double arch below; it helps when a descender or another mark crowds the space below.

A 1926 phonetic work by Otto Jespersen and Holger Pedersen uses an omega-shaped lip-rounding mark. The International Phonetic Association used an omega-shaped mark for rounding or labialization until 1989. Later notation distinguishes two gestures: rounding with the lips pushed forward and rounding with the lips pressed inward. Other transcription traditions have used an inverted form for unrounded sounds; some use angular, w-shaped marks. These conventions differ, so check the key for the transcription at hand.

Why does the arch vanish or sit in the wrong place?

It needs a base letter and font support.

In text order, the base comes first and the combining mark follows, even though the arch appears above. When the mark stands alone, a sample may place it on a dotted circle or a blank spacing character to show where it attaches; that display aid is not part of the mark.

If the mark is missing or sits too high or low, check whether the font supports it and positions combining marks correctly. Different fonts can attach the same mark differently.