What is what does quarter till mean?

Quarter till is a common expression used to refer to a specific time in the hour, usually when there are 15 minutes left until the next hour. It is also known as 15 minutes before the hour or 45 minutes past the previous hour. For example, if the time is 3:45, it is referred to as quarter till 4. It is a way of telling time that helps to indicate how much time is left until the hour changes.