Regrettable
Unsatisfactory
noun, な adjective
If you leave behind something and it makes you feel remorse it's a really regrettable situation. You should probably go back for whatever it was so you won't lead an unsatisfactory life.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
裁判は誠に遺憾な結果に終わりました。
The trial ended with an absolutely unsatisfactory result.
An update is needed before you can continue but you have more than one WaniKani tab open.
Finish up what ever you are doing on the other tab(s), then close them to continue.
The update will complete automatically once the other tab(s) are closed.