1. The final phase or stage of a project, process, or development when it is nearing or reaching its end
The construction project is now in the completion stage.
O projeto de construção está agora no estágio de conclusão.
2. In project management, the phase where remaining tasks are being finished and final quality checks are performed
During the completion stage, all outstanding issues must be resolved.
Durante o estágio de conclusão, todas as questões pendentes devem ser resolvidas.