Silent k

A silent ⟨k⟩ occurs when the letter ⟨k⟩ appears in a word but does not actually reflect the pronunciation of a voiceless velar plosive (/k/), or any sound for that matter. A silent ⟨k⟩ is quite common in the English language, most often preceding an ⟨n⟩ at the beginning of a word. There are rare exceptions to this rule; one example is Knoebels Grove (pronounced kuh-NO-bel) located in Pennsylvania in the United States.

While not as common, the letter ⟨g⟩ will also become silent when placed in front of an ⟨n⟩ at the beginning of a word, rather than being realized as a voiced velar plosive (/g/). An exception is the acronym GNU.

In Old English, ⟨k⟩ and ⟨g⟩ were not silent in these words. Cognates in other Germanic languages show that the ⟨k⟩ was probably a voiceless velar plosive in Proto-Germanic (compare German to , to , etc. where the initial ⟨k⟩ is not silent); likewise, ⟨g⟩ was probably a voiced velar plosive (compare German to , to , etc. where the initial ⟨g⟩ is not silent).

Following is a list of words that include a silent ⟨k). For verbs, only the infinitive form of the verb is given, not any conjugations:

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