The term that describes how long it takes a function to repeat its behavior is the

The term that describes how long it takes a function to repeat its behavior is the:

PERIOD.

Step-by-step explanation:

A function f is said to be periodic if, for some nonzero constant P, it is the case that

for all values of x in the domain. A nonzero constant P for which this is the case is called a period of the function.

i.e. it is the smallest  number such that after which the function repeat itself.

Hence, the answer to the given question is:

Period.