What Is Freezing Point?

For any given liquid, the freezing point is the temperature at which the liquid changes state
from a liquid to a solid. The temperature remains at this point until
all the liquid has solidified. It is invariable under similar
conditions of pressure – for example, the freezing point of water under
standard atmospheric pressure is 0°C/32°F.
For a given liquid under similar conditions, the freezing point and melting point are the same temperature.

Freezing points means a point at which liquid or even gas changes its state and turns into solid.
Let us take example of water. Water is a liquid at room temperature which is usually 25 Celsius. But when the temperature falls to zero Celsius or below (like in Arctic and Antarctica), water becomes solid and is called Ice. Different liquids and gases have different Freezing points.
Do visit following blurtit references:
What Is The Freezing Point In Either Celcius Or Kelvin?
What Is The Freezing Point Of Nitrogen??
What Will Happen To Boiling Point& Freezing Point ,when A Salt Dissolves In Water?

It means when the water freezes because of the air and its coldness