It's a cross !!!

Josie	Have you seen Peter's new dog ?
Lara	Yes I have but couldn't recognize the breed.
Josie	That's not surprising because it's not a thoroughbred, it's a mongrel.
Lara	Ah, that explains it. What kind of a mixture is it ?
Josie	I think it's a cross between a collie and a retriever.
Lara	If that's the case it should be a very good-natured dog.

Explanation :

Something that is a cross between two things is neither one thing nor the other, but a mixture of both.

Example :  Ha ! It was a cross between a laugh and a bark ..........