I’m a freelance copywriter
If you want a general term for this sort of thing: <a href="https://en.wikipedia.org/wiki/StretchText" rel="nofollow">https://en.wikipedia.org/wiki/StretchText</a>. (The original note describing the concept: <a href="http://i.imgur.com/jOCOQGI.png" rel="nofollow">http://i.imgur.com/jOCOQGI.png</a>)