A homomorphism is a function so that f(ab) = f(a) f(b). So you can imagine the cloud customer wants to compute ab, but the use a homomorphic encryption function

A homomorphism is a function so that f(ab) = f(a) f(b). So you can imagine the cloud customer wants to compute ab, but the use a homomorphic encryption function, f, to ask the cloud provider to computer f(ab) given f(a) and f(b). Then the customer decrypts f(ab). This doesn’t imply any weakness in encryption. FHE is a bit stronger than what I’ve described, but that’s the idea.