The phrase “didn’t show up” means that someone did not arrive at a planned event or location where they were expected to be. It can refer to various situations, such as a person not attending a meeting, a social gathering, or an appointment. The absence can be intentional or unintentional, and it often implies disappointment or inconvenience for those who were expecting the individual to be present. For example, if someone had a scheduled interview and didn’t show up, it means they failed to attend the interview without prior notice.