Trigraph (orthography)

A trigraph (from the Greek: τρεῖς, treîs, "three" and γράφω, gráphō, "write") is a group of three characters used to represent a single sound or a combination of sounds that does not correspond to the written letters combined.

For example, in the word schilling, the trigraph sch represents the voiceless postalveolar fricative /ʃ/, rather than the consonant cluster /sx/. In the word beautiful, the sequence eau is pronounced /juː/, and in the French word château it is pronounced /o/. It is sometimes difficult to determine whether a sequence of letters in English is a trigraph, because of the complicating role of silent letters. There are few productive trigraphs in English such as tch as in watch, and igh as in high.

The trigraph sch in German is equivalent to the English sh and pronounced /ʃ/. In the Dutch language, which is closely related to German, this same trigraph is pronounced /sx/. In Italian, however, sch represents the sounds /sk/ before e or i, as in "bruschetta" /brusˈkɛtːa/. In neither language is this trigraph regarded as an independent letter of the alphabet. In Hungarian, the trigraph dzs is treated as a distinct letter, with its own place in the alphabet. It is pronounced like an English "j" /dʒ/. The combination gli in Italian can also be a trigraph, representing the palatal lateral approximant /ʎ/ before vowels other than i, as in , pronounced [/ˈaʎːo/].

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