The term 'conclude one's case' can be summarized as the act of providing a final argument or statement in order to prove a point. This term is often used in legal contexts, where a lawyer will present their closing argument to the court in order to prove their client's innocence or guilt. The crossword solution for this term is 'REST, ' which can be interpreted as the conclusion of a case, as it implies that the argument has been made and the decision is now up to the court.