Meaning of hyperexcitability

hy•per•ex•cit•a•bil•i•ty

Pronunciation: (hī"pur-ik-sī"tu-bil'i-tē), [key]
— n. Pathol., Psychol.
  1. an excessive reaction to stimuli.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.