A coffee bean is a seed from the Coffea plant and the source for coffee. It is the pip inside the red or purple fruit. This fruit is often referred to as a coffee cherry, and like the cherry, it is a fruit with a pip. Even though the coffee beans are not technically beans, they are referred to as such because of their resemblance to true beans.
The coffee fruit, also known as a coffee cherry, houses the coffee seed within. This seed is what we commonly refer to as a coffee bean. However, botanically speaking, coffee is not a true bean but rather a seed.
What is a coffee bean?
-wikipedia
OK I did my own search