excitation

noun

1. 1

   The act of exciting or putting in motion; the act of rousing up or awakening.

2. 2

   The act of producing excitement (stimulation); also, the excitement produced.

3. 3

   The activity produced in an organ, tissue, or part, such as a nerve cell, as a result of stimulation

4. 4

   The change in state as an excited state is formed by the absorption of a quantum of energy