sentinel

C2 · Proficiency Countable noun Medicine Technical

n. a sign or event that shows a health risk or the start of a disease.

n. an indicator, such as a specific case of disease or an environmental event, that signals a potential public health threat.

“The first case of the flu acted as a sentinel for the coming winter season.”

“Public health officials monitor sentinel events in local clinics to detect the early stages of a potential epidemic before it spreads to the general population.”

C2 · Proficiency Countable noun Computing Technical

n. a special value in a computer program that marks the end of a list of data.

n. a specific value used in computer programming to signal the end of a data structure or to terminate a loop.

“The program looks for a zero as a sentinel to stop reading the list of numbers.”

“The algorithm iterates through the array until it encounters the sentinel value, ensuring that the process does not attempt to access memory beyond the allocated buffer.”