Public sentiment, also known as public opinion, is the collective attitude of a group of people towards a particular issue or topic. It can be measured through surveys, polls, and other forms of research. The term 'ETHOS' is derived from the Greek word for 'CHARACTER' and is used to describe the moral CHARACTER of a person or group. It is often used to refer to the credibility of a speaker or writer. The term 'PULSE' is used to describe the rate at which something changes or fluctuates. In the context of public sentiment, it can refer to the changing attitudes of a population over time.