This is dedicated to @SillyBeardy
Just for a bit of fun this evening, here is a brief post on a brief word. Unsurprisingly, the word “cheeky” developed from “cheek”, with the “y” added to turn it into an adjective. The idea of it applying to “insolence” as well as a part of the face is likely to have developed in a similar way to such expressions as “mouth off”, and dates from around 1840.
So let’s take a look at “cheek”, then. It comes from Old English ceace, which meant “jaw” or jawbone”. There are two main schools of thought as to where it came from. The first proposal is that it originates from the same root as Old English ceowan, which meant “chew”. This in turn developed from a West Germanic root, *keuwwan, also meaning “chew”, ultimately deriving from Proto-Indo-European root *gyeu-, which would have meant, guess what; “to chew”.
The second proposal gives Proto-Germanic *kaukon, meaning “jaw, jawbone” as the likely source, but in this case, we cannot trace it further, as it is only found in West Germanic languages, such as in Dutch kaak, Danish kæbe and Swedish käke, all meaning “jaw”.
An interesting point is the Hungarian equivalent of “cheeky”. In Hungarian, szemtelen is used in the same way as “cheeky” in English, but it literally translates as “eyeless”! Not only that, but very similar to the English word is the stronger alternative to szemtelen – this is pofátlan, which means “cheekless”. The word pofa is “cheek”, and it derives from there. Indeed, one possible explanation for pofátlan is that the person so called is so rude that they wouldn’t even blush, as if they had no cheeks!
Glossologics 