Pronounced zuàn shíwáng lǎo wǔ, this literally means "an old Joe with diamonds" or "a diamond bachelor," which refers to a man who has passed the optimum age for marriage but is highly valued because of his career success and status in society. Many women desire such bachelors.
Let's put it into context:
Allen: Hey Phil, did you know Mike is getting married next week? We are both invited to his wedding!
Phil: What!? He is getting married? I thought he enjoyed being a zuàn shíwáng lǎo wǔ, you know, like me.
Allen: You? A diamond bachelor? Ha! Get out of here!!