Originally, 環 meant “jeweled ring or bracelet (possibly of wondrous quality) that fit perfectly.” Wow! That’s some piece of jewelry. The character later came to mean “ring” or “circle” in a broader sense.
The radical 王 means “jewel.” It should mean “king,” because that’s the way to write “king.” By contrast, the way to write “jewel” is 玉. But Henshall says the extra dot in 玉 gets dropped when 王 serves as a radical. Hmm … omoshiroi! Makes me wonder where else we see this squished gem as a radical …
Besides 王, the other components in 環 mean “to gaze in terror.” Henshall doesn’t know why but notes that the right-hand side of 環 combines 目 (an eye tilted 90 degrees) and a variant of 哀 (AI, awa(re): sorrow, pity). He says that the right-hand side of 環 also contributes to the sound of this kanji, as well as expressing the idea of “fitting” and maybe of “looking in awe at something wondrous.”
