Why do the British call fries chips?

The most common explanation is that the word chip comes from "chipping", which means to cut something into small thin slices. This is exactly what is done to potatoes to make french fries.

Another possible explanation is that the word "chip" is a shortened form of "chipper", which was a type of knife that was used to cut potatoes into thin strips.

Still, other evidence suggests that the term "chips" was first used to describe french fries in the United States, long before it was used in the United Kingdom. However, the reason for the origin of the term is not well documented so the actual origin of the word is still debatable.