Bold stroke, an expression that refers to a daring and decisive action, can be substituted by several synonyms. One possible synonym is "courageous move," which suggests a fearless and resolute act. Another alternative is "brave decision," emphasizing the bravery required to take a particular action. Alternatively, "audacious initiative" is a phrase that connotes boldness and innovation, highlighting novelty and exceptionality. "Adventurous step" is a synonym that suggests risk-taking and exploration, where a person is willing to take chances to achieve their goals. Finally, "daring maneuver" refers to an action that is both daring and skillful, requiring expertise and boldness.