Kanji Details for 囗

A radical is a part of a kanji by which it can be identified and looked up in a dictionary. There are 214 Kangxi radicals. 囗 and 口 are not radicals of each other. Even thought they look alike they have distinct semantic and phonetic properties.

A radical is different from a component which is also a part of a kanji but can be made of two or more radicals, or can be a variation of a radical. These components sometimes posses semantic or phonetic properties.

If you look at jisho.org you can see all the radicals.

I wanted to know what is the definition of radical? Because Mouth and Box are considered radicals of each other and still, neither is made from the other one. They look more like distorted forms of each other