Combining Double Tilde

It puts one wide tilde across a letter pair. In n͠g, the mark is stored after n but drawn over n and g. It attaches to a letter instead of standing alone like punctuation, so fonts and editors must handle a span across two letters.

The wide tilde appears in phonetic transcription, which writes down sounds, and transliteration, which represents one script in another. In older Tagalog writing, a long tilde marked ng as one nasal sound—the sound at the end of English sing—and could link a following vowel to the same syllable.

Why does the same mark mean different things?

Its surrounding letters and notation set its role. The 1593 Doctrina Christiana, an early printed book in Tagalog, shows forms such as ng̃; that example has a tilde over g, not the two-letter span used in later wide-mark spellings. Those spellings eventually gave way to plain ng.

Old Church Slavonic, an older Slavic written language, used a titlo—a mark over letters serving as numerals—across two Cyrillic letters. In в͠і, the titlo spans the pair. Unicode also has left and right half marks that can imitate the span, but they are separate characters.