Bonus
noun
It's a prize where you are given gold. In business, this is called a bonus. You didn't expect it (not your salary) and it is given to you (and is gold, if you're lucky).
Note that you’ll more commonly see its shorter version 賞与.
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.
賞与金の話を聞いて、急に勉強する気になりました。
I felt the urge to study after hearing about the bonus.
こんなに賞与金を出してくれるなんて、お前の会社は気前が良いんだなぁ。
You got this much bonus? Your company is generous, yeah?
給料日は毎月五日と二十日で、会社の業績次第で賞与金が年末に支払われます。
Our paydays are the fifth and the twentieth of every month, and a bonus may be paid at the end of the year depending on how well the company has done.