Wiktionary
timeboxing
n. (context management English) A way to plan activity by allocating specific time boxes for a task that is used as a distinctive feature in several project management approaches. vb. (present participle of timebox English)
Wikipedia
Timeboxing
In time management, timeboxing allocates a fixed time period, called a time box, to each planned activity. Several project management approaches use timeboxing. It is also used for individual use to address personal tasks in a smaller time frame. It often involves having deliverables and deadlines, which will improve the productivity of the user.