what is the meaning of scattering of light?

Scattering is the phenomenon by which a beam of light is redirected in many different directions when it interacts with a particle of matter.

In suspension solutions i.e. non-homogeneous solutions in which solute particles doesn't completely dissolve in solvent, when light rays pass through such solution the suspended particles scatter light in all directions and hence we able to see the path of light. In true solutions, the solute particles complete dissolve in solvent and makes a homogeneous solution. As there is no suspended particles to scatter light rays we not able to see light path.

Scattering is the phenomenon by which a beam of light is redirected in many different directions when it interacts with a particle of matter.

For example - when sunlight strikes molecules in our atmosphere, the light is redirected in many directions. The blue light is scattered more than the red light causing the sky to be blue

White light consists of 7 colours, each has its own wavelength.

Light travels through space in a straight line as long as nothing disturbs it. As light moves through the atmosphere, it continues to go straight until it bumps into a gas molecule. Gas molecules are smaller than the wavelength of visible light. If light bumps into them, it acts differently. When light hits a gas molecule, some of it may get absorbed. After awhile, the molecule radiates (releases, or gives off) the light in a different direction. The color that is radiated is the same color that was absorbed. The different colors of light are affected differently. All of the colors can be absorbed. But the higher frequencies (blues) are absorbed more often than the lower frequencies (reds).

The diagram below will help in understanding the process further.