Null is not an object (evaluating ‘e.length’)

So I am getting this error on my wordpress site and can’t work out what’s causing it. I have attached a screenshot of what shows up when the error is expanded though my gut feeling is that it’s got something to do with how the jQuery is loaded.

If anyone can give me any pointers or things to check – that’d be great.

Code in script.js:17

jQuery(document).ready(function($) {
    // set the container that Masonry will be inside of in a var
    var container = document.querySelector('#masonry');

    // create empty var msnry
    var msnry;

    // initialize Masonry after all images have loaded
    imagesLoaded( container, function() {
        msnry = new Masonry( container, {
            itemSelector: '.masonry-item'
        });
    });
});