Ch (digraph)

Ch is a digraph in the Latin script. It is treated as a letter of its own in Chamorro, Old Spanish, Czech, Slovak, Igbo, Uzbek, Quechua, Guarani, Welsh, Cornish, Breton and Belarusian Łacinka alphabets. In Vietnamese and Modern Spanish, it also used to be considered a letter for collation purposes but this is no longer common.

The digraph was first used in Latin since the 2nd century B.C. to transliterate the sound of the Greek letter chi in words borrowed from that language. In classical times, Greeks pronounced this as an aspirated voiceless velar plosive [kʰ]. In post-classical Greek (Koine and Modern) this sound developed into a fricative [x]. Since neither sound was found in native Latin words (with some exceptions like pulcher 'beautiful', where the original sound [k] was influenced by [l] or [r]), in Late Latin the pronunciation [k] occurred.

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