noun, verbal noun
If you quit your place of employment, you are quitting, aka putting in your resignation.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
The MP will not resign and will continue to be a member of parliament.
Mami was forced to resign for the crime of eating Koichi's bacon.
My boss told me flat-out that I was disposable, so I quit the company.