Definition from Sergey Gladkiy
βA diagram designed to identify cause-and-effect relationships between factors in a given situation. It is made up of a "head", which states a problem, and bones along the spine that represent factors and categories of factors.β
Going further
I've curated 400+ definitions just like this one in a tiny dictionary. In this glossary you can easily access, search and understand 400+ terms that service designers and other innovators use.