Hour is a unit of time measurement that is equivalent to 60 minutes. However, in different contexts, there may be other words that mean the same thing as hour. For example, "o'clock" refers to a specific hour on the clock face. "Time" is another synonym for hour, which is more general and can refer to any length of time. "Interval" is another term that can be used interchangeably with hour, especially when referring to a specific duration of time, such as a lunch hour. Additionally, "minute" is also a synonym for hour, as 60 minutes make up an hour. These synonyms for hour can be used in different contexts depending on the context of the situation.