macroned

Thus o will represent all shades of sound of the o group, macroned "ō" being used when desirable, for the so-called "long o" of whatever shade, phonetic specialists using also other marked forms, “ŏ, ó, ò, ô, ö," etc., according to some accepted system.

1883 April 28, Charles P. G. Scott, “O·ld-Leter Fo·notipi”, in Phonetic Journal, London: F. Pitman: Phonetic Depot, page 203

Nor do I use macroned letters to convey long Arabic vowels. These omissions are made in order to facilitate the production of a lengthy text such as this one, and by no means reflect my negative attitude toward any transliteration system current in my field of specialization.

1999, Alexander D. Knysh, Ibn ʻArabi in the Later Islamic Tradition: The Making of a Polemical Image in Medieval Islam, Albany: State University of New York Press, →ISBN, page xvi

Common Japanese words, such as the place name Tōkyō (東京), require macroned vowels to properly express long vowels when using the Hepburn system, which is the most widely accepted Japanese transliteration system.

2009, Karl Lunde, “Chapter 6: Font Formats, Glyph Sets, and Font Tools”, in CJKV information processing, O'Reilly Media, →ISBN, page 411