What is the meaning of Run-up?

The approach run of a bowler before delivering the ball.

The approach run of a high jumper or other athlete in order to gather speed or momentum.

A period of time just before an important event.

An increase in the value or amount of something.

The extent of a wave's reach onto land as the result of a tsunami or storm such as a cyclone.

The process of warming up and testing an airplane before a flight.

Source: wiktionary.org