A roundup is the act of gathering things or people together from different places into one spot. The word comes from cattle ranching: cowboys would round up herds of cattle scattered across vast grasslands, bringing them together for counting, branding, or moving to new pastures. Picture dozens of cattle spread across miles of prairie, and cowboys riding out to collect them all into one group.

Today we use roundup in many contexts beyond ranching. Police might conduct a roundup of suspects in a crime investigation, gathering people from various locations. A teacher does a quick roundup of students after recess, making sure everyone is back in the classroom. At the end of a busy week, you might do a roundup of your homework assignments to see what still needs finishing.

News programs often feature roundups: a sports roundup summarizes the day's games and scores, while a news roundup reviews the week's important events. These summaries gather scattered information into one convenient report, just like those cowboys gathering scattered cattle. The word suggests an active, deliberate effort to bring together things that had been spread out or separated.