“ache: [OE] The word ache is a good example of the way that English spelling and pronunciation have developed and in many cases have diverged from each other. The noun comes from Old English and used to be pronounced “aitch” (like the letter H), whereas the verb was originally spelled ake and pronounced the way ache is today. Around 1700, people started pronouncing the noun like the verb. The spelling of the noun has survived, but the word is said in the way the verb (ake) used to be. The modern spelling is largely due to Dr. Johnson, who mistakenly assumed that the word came from Greek akhos ‘pain.’ Other pairs of words that have survived into modern English with k-for-the-verb and ch-for-the-noun spellings include speak and speech and break and breach.:
Excerpted from: Creswell, Julia. Oxford Dictionary of Word Origins. New York: Oxford University Press, 2010.
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