I-mutation

Okay kiddo, can you say "cat" and "kitten"? They are similar words, right? But have you noticed that the letter "i" is in "kitten" but not in "cat"? That's because of something called i-mutation.

I-mutation is when the sound of a vowel in a word changes because there used to be an "i" in the word that got dropped. This usually happens in older languages like Old English or Old Norse.

For example, let's say we have the word "dagiz" which means "days" in Old Norse. When we add the plural ending "-r" to make it "dagir", the vowel in the word changes from "a" to "i". This is because there used to be an "i" in the plural ending, but it got dropped.

So basically, i-mutation is when the presence of an "i" in a word or suffix can change the sound of other vowels in that word. It's like a game of musical chairs for vowel sounds!