What is what does a quarter till mean?

"Quarter till" is a colloquial expression commonly used in the United States to refer to time, especially when indicating minutes before the hour. It means that fifteen minutes are remaining until the hour, for example, if the time now is 3:45, we might say that it is "a quarter till four." It is derived from the notion of dividing time into quarters or fourths of an hour, with each quarter representing 15 minutes of time. The term "quarter till" is also sometimes referred to as "quarter to," "quarter before," or "quarter till the hour."