I believe I’ve stated before a surname/ word sounds like it starts with N, but it could also be spelled Kn—. The letter’s sounds come from two different parts of the mouth and are hard to pronounce. Over time starting in the mid-1400s, the K became silent in English words although it continued somewhat in Northern England and Scotland into the mid-1800s. Speakers of other Germanic languages still pronounce it. Remember that when you’re looking for a family name in an index.