Big design up front (BDUF) is a software development approach in which the program's design is to be completed and perfected before that program's implementation is started. 

It is often associated with the waterfall model of software development.

「事前の大規模設計」を指す言葉で、

Synonyms for big design up front (BDUF) are big modeling up front (BMUF) and big requirements up front (BRUF). These are viewed as anti-patterns within agile software development.

 のアンチパターンとみなされている