Last week we covered the spelling CC. Most of these words are from Latin. Words with CC that are not from Latin may have other pronunciations. The pattern we found was that words with the CC before an I or E make a /ks/, if they are from Latin, otherwise they make a /k/. At first CC seems to be the same as CK, however there are important differences.
The combination CK has a /k/ sound. However unlike CC these words did not come into English from Latin. Most of these words come from Old English. Most of the rest are from older versions of Dutch, German, Non-Latin French or Norse. Old English examples1: , lick (liccian), knock (cnocian), neck (hnecca), rock (rocc), sack (sacc), sick (sacc), stick (sticca) thick . Dutch: clock (clocke), luck (luc). German: deck (verdeck). French: pocket (pokete). Norse: freckle (frecken), kick (kikna). Sometimes the older spelling was CC and has been converted into a CK in the modern spelling.
This digraph is clearly of Germanic, not Latin, origin. All of these other languages are related to German. Old English and Dutch were originally lowland (coastal) German dialects. The French language is descended both from Latin and the language of the wild German tribe called the Franks. The Franks invaded what is now France in the 3rd century AD. The Norse were Germanic tribes that settled in Northern Europe, in the area called Scandinavia.
The diagraph CK usually comes at the end of a word or syllable following a short vowel sound. It is only pronounced /k/. The sound /k/ at the end of a word is usually written CK or K. While it is useless having another digraph that could be replaced by the letter K, at least this diagraph has only one sound associated with it.