Prosperity, Flourishing, Thriving
noun, verbal noun
Overgrown prosperity is still prosperity. Why, it's even thriving. Nice!
はんじょう
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
商売が繁昌するように、神社でお祈りをしてきました。
I went to pray at a Shinto shrine in order for the company to prosper.