Definition:Time

Definition
A true definition of what time actually is has baffled philosophers from the dawn of, er, time.

Therefore it will be left as an exercise for the reader.

Dimension
Time is one of the fundamental dimensions of physics.

In dimensional analysis it is assigned the symbol $T$ or $\mathbf T$.

It is a scalar quantity which can be mapped directly to the real number line.

Unit Time
The usual units of time are seconds.

However, when discussing a general physical process it is convenient to discuss the general situation, in which case the term unit time is used.

Thus the specific units are not mentioned.