A Backronym is an Acronym which was coined after the name was already in circulation.
- BASIC is a classic Backronym.
- Perl did not originally mean anything in particular, but was later expanded as Practical Extraction and Report Language – or, at your discretion, Pathologically Eclectic Rubbish Lister. (Yes, both are officially sanctioned.)
- GCC became a Backronym when it's meaning was changed from GNU C Compiler to GNU Compiler Collection.