DIGRAPH
digraph, digram
(noun) two successive letters (especially two letters used to represent a single sound: ‘sh’ in ‘shoe’)
Source: WordNet® 3.1
Etymology 1
Noun
digraph (plural digraphs)
(graph theory) A directed graph.
Hyponyms
• multidigraph
Etymology 2
Noun
digraph (plural digraphs)
(computing) A two-character sequence used to enter a single conceptual character.
(linguistics) A pair of letters, especially a pair representing a single phoneme.
Hyponyms
• (linguistics: pair of letters): diphthong, ligature
Source: Wiktionary
Di"graph, n. Etym: [Gr.
Definition: Two signs or characters combined to express a single
articulated sound; as ea in head, or th in bath.
Source: Webster’s Unabridged Dictionary 1913 Edition