"TL;DR" means "too long; didn't read," but the semicolon is usually associated with long or complex sentences. What is it doing in this abbreviation? Note: This piece originally appeared as a Grammar Girl blog post January 22, 2014 and was rereleased as an audio podcast on July 3, 2014. Visit the website to read the full transcript and leave a comment: http://bit.ly/1g1PtiA