Modifier Letter Capital O

In UPA, it marks a very short sound or a transition. The Uralic Phonetic Alphabet (UPA), also called Finno-Ugric transcription (FUT), uses raised letters for very brief sounds, often between neighboring sounds. So ᴼ marks the O-type sound as short; the transcription system determines its exact value.

UPA was designed to describe pronunciation, sound patterns, and word histories in Uralic languages such as Finnish, Hungarian, and Sámi. The Unicode proposal cites UPA examples by Szilasi and Setälä from 1901. The 2002 proposal records UPA research in Finland, Hungary, Estonia, Germany, Norway, Sweden, and Russia, alongside further use in North America and Japan. These dates refer to documented work, not the invention date of this individual character.

How do I type superscript capital O?

Use Unicode hexadecimal entry for this character. The code is 1D3C; the keystrokes depend on the operating system and app. Superscript formatting on an ordinary O changes its appearance, not its character identity. UPA uses separate text characters because placement and letter style carry phonetic distinctions.

Why does ᴼ look different?

The font and the notation both affect what you see. ᴼ is a text character, not emoji artwork. Its appearance follows the active font, and related phonetic forms can look so similar that their distinction is hard to see.

Shape alone is a poor guide. O is an ordinary capital O; ᴏ is a baseline small-capital O; ᵒ is a lowercase modifier O. In UPA, letter style and placement can carry different information, so use the form specified by the transcription.