瑠 is built from the 王, ム (private), 刀, and 田 components.
A common word using 瑠 is 浄瑠璃 (じょうるり), meaning “jōruri; type of dramatic recitation accompanied by a shamisen (associated with Japanese puppet theater)”.
Kanji that look similar include 徴, 潤, 瑞, and 璃.
