An Acronym for Formula Translator.
The very first high level ProgrammingLanguage ever invented. Initially halfway between BASIC and AssemblyLanguage, it was very limited in constructs. The use of GoTo was therefor very prevalent in Fortran programs, leading to the hugely famous GoToStatementConsideredHarmful article.
This notoriety has also led to it being used as a synonym for hard to maintain code in various contexts - real programmers can write Fortran in every language.
Nevertheless the language has evolved over time to allow local variables, even recursion and other advanced programming techniques. It is still the language of choice for number crunching on supercomputers, for which Fortran Compilers have been heavily optimised.