Consider the joke told by Richard Stallman that I read in this article:
Once I was eating in Legal Sea Food and ordered arctic char. When it arrived, I looked for a signature, saw none, and complained to my friends, “This is an unsigned char. I wanted a signed char!” I would have complained to the waiter if I had thought he’d get the joke.
Until today, the word “char” had only one meaning to me. It was a computer term, which is used as a declaration of a character or string variable in some programming languages. Such as C, for example.
It turns out, that there is another meaning. Here is a quote from the dictionary for you:
also charr (n. pl. char or chars also charr or charrs)
Any of several fishes of the genus Salvelinus, especially the arctic char, related to the trout and salmon.