JSFiddle - React, Tailwind, and code Playground

HTML

<div id="txt">
Lorem ipsum dolor sit amet, consetetur
</div>

CSS

#txt {
    width: 75px;
    height: 75px;
    border: 1px solid #F00;
    overflow: hidden;
}

JavaScript

var cntnr = $("#txt");
cntnr.html('<span>'+cntnr.html().replace(/ /g,'</span> <span>')+'</span>')
var words = Array.prototype.slice.call(cntnr.find("span"),0).reverse();
var lastw = null;
for(var i=0,c=words.length;i<c;i++)
{
    var w = $(words[i]);
    var wbot = w.height() + w.offset().top;
    var wleft = w.position().left;
    var wright = wleft+w.width();
    if(wbot <= cntnr.height() && wleft <= cntnr.width() && wright <= cntnr.width())
    {
        lastw = w.text();
        break;
    }
}
cntnr.html(cntnr.text());
alert(lastw);