Itching:
The unpleasant sensation that evokes the desire or reflex to scratch. It can originate in the peripheral nervous system (dermal or neuropathic) or in the central nervous system (neurogenic or psychogenic).

Scratching:
- To rub the surface of the skin with an object i.e. nails, claws, rocks, trees, etc., in order to remove itching.
- To rub the skin with rough material causing a sensation of irritation.