JSFiddle - React, Tailwind, and code Playground
HTML
<script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>
<div id="fakeform1">
<div class="Disclaimer"> I want to get complete class name </div>
</div>JavaScript
$(document).ready(function() {
var test = $('#fakeform1').find('div').filter(function() { return $(this).attr('class').indexOf('sclaimer') !== -1; });
if (test.length) {
alert(test.attr('class'));
}
});