I agree with all the answers here that jQuery itself is indeed a library, not a framework. As specified by Saeed's answer, one of the key distinguishing features is inversion of control. You could however use jQuery's functionality to create a framework of your own.
Examples: there are projects built on top of jQuery that are defined as frameworks: jQuery Mobile: A Touch-Optimized Web Framework, JavaScriptMVC and sammy.js to name a few.
There are also other libraries built on top of jQuery, like jQuery UI
Some of it seems like semantics when defining what a library is vs a framework, but those examples help draw the line for me.