Noun
Two signs or characters combined to express a single articulated sound; as ea in head, or th in bath.
Source: Webster's dictionaryAdditionally, when written in capitals, "ß" is replaced with "ss" in Germany, whereas in Austria it is traditionally replaced with "sz" (the same digraph used in Hungarian for the "s" sound); there are some exceptions to these rules (see below). Source: Internet
Also, digraph diacritics are often used and sometimes even mixed with diacritical letters of standard orthography. Source: Internet
A phoneme may be represented by a multigraph (sequence of more than one grapheme), as the digraph sh represents a single sound in English (and sometimes a single grapheme may represent more than one phoneme, as with the Russian letter я ). Source: Internet
Because the first letter in a vowel digraph sometimes says its long vowel sound, as in sail, some phonics programs once taught that "when two vowels go walking, the first one does the talking." Source: Internet
In addition, there are also some runes which stand for a particular English digraph or diphthong. Source: Internet
Cryptonyms are sometimes written with a slash after the digraph, e.g., ZR/RIFLE, and sometimes in one sequence, e.g., ZRRIFLE. Source: Internet