What is the definition of time?

Time is the measurement that allows us to categorize our experiences into memories, present, and potential.

From Merriam Webster:

1. a : the measured or measurable period during which an action, process, or condition exists or continues : duration b : a nonspatial continuum that is measured in terms of events which succeed one another from past through present to future

Time

Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify the motions of objects. Time has been a major subject of religion, philosophy, and science, but defining it in a non-controversial manner applicable to all fields of study has consistently eluded the greatest scholars.

Wikipedia

Some people argue that time is out there and measurable. Others say that time is not out there; instead it is a “fundamental intellectual structure (together with space and number) within which humans sequence and compare events.” I.e., it is a human construct that we created to help us keep track of the world. In other words, we create time in our heads.

The Merriam Webster definition leaves out a lot, and has selected only one, not very interesting view of time.

I read somewhere that time was the dimension in which bodies in space “free-fall.”

You may have heard of the Uncertainty Principle, where the more you know about an object’s momentum, the less you know about its position in space. There’s a similar uncertainty principle with time and energy. The more precisely you know a state’s energy, the less you know about when that state exists.

I think.

Another fun (ha) fact: photons don’t experience time. Even though photons take time to travel (the speed of light), from the photon’s perspective, every moment in their journey is collapsed; the journey takes no time at all.

Time is that moment we have to be at work and that moment we get to leave work…everything besides Doctor appointments are irrelevant to the concept of time.

It’s just filler that keeps everything from happening at once.