̱

◌̱ U+0331, ̱ COMBINING MACRON BELOW ← ◌̰ [U+0330] Combining Diacritical Marks ◌̲ → [U+0332]

Cayuga

Diacritical mark

 ̲

1. indicates a devoiced vowel

References

• Marianne Mithun; Reginald Henry (1982) Wadęwayę́stanih - A Cayuga Teaching Grammar, 3rd edition, Woodland Cultural Centre, published 2015, page 7

Choctaw

Diacritical mark

 ̲

1. indicates a nasal vowel