I was just curious about this. I know that the "k" sound is pretty common in the English language but I was thinking about curse words and a lot of the stronger ones like cunt/fuck or slurs like kyke/dyke/chink or vulgar references like cock/dick contain it. I only know my own language, but is there any sort of historical pattern of that sound at the beginning or end of curse words? Maybe it's only as common as other words. I don't know.