back to square one , j2 N- h2 O$ q c An expression used to mean that it is necessary to stop whatever one has done on a new project and to start again completely. + q' f c7 v: h+ r% | EXAMPLE: 5 d: S! \- o- T* m2 Y; s When our experimental design for a new solar automobile failed totally on the first day of testing, our engineering department knew it was back to square one.