This isn’t really a slang term, but it’s a set phrase that is very useful to know. If something is “mutually beneficial” it means that it is good for both people or both groups. It’s a phrase that can be used in a business setting as well as other situations. Another way of phrasing this is by calling it a “win win” situation.
Here is an example conversation where the phrase is used quite well:
Brian: I heard you are going to ask your boss to lower your salary and give you a higher commission on sales. Do you think he will agree to it?
Kevin: Absolutely. It’s mutually beneficial. From his perspective, I’ll only get paid well if I make a lot of sales and earn him more money. For me, it gives me a good reason to work harder and sell more stuff. The harder I work, the more sales I make and the more money both me and the company get. It’s a win win situation.
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