The term 'DECISIVE STAGE' can be broken down into two parts: 'DECISIVE' and 'STAGE'. The word 'DECISIVE' is defined as having the power to make decisions or judgments, while the word 'STAGE' refers to a period of time in a process or development. Together, the term 'DECISIVE STAGE' can be interpreted as a period of time in which decisions are made that will have a lasting impact on the outcome of a process or development. The crossword solution for this term is 'CRUX', which is defined as the most important or critical point of something. Therefore, the term 'DECISIVE STAGE' can be summarized as a period of time in which the most important decisions are made that will determine the outcome of a process or development.