This question is about semantics.
I have a client who says that the term "widget" should only be used when referring to a dynamic object that syndicates your own content on to a third party site. I believe widget can be used to refer to any self-contained dynamic object on a site (your own or a third party). However, my client says that if the object is on your own site, it is a "gadget."
I'm not sure if there is an official definition, but I'm interested to know what is the common understanding of the difference, if any, between the two terms?