reactive
1. [ adjective ] tending to react to a stimulus
Examples:

"the skin of the geriatric is less reactive than that of younger persons"- Louis Tuft

Related terms: sensitive
2. [ adjective ] (chemistry and physics) participating readily in reactions
Examples:

"sodium is a reactive metal" "free radicals are very reactive"

Related terms: unreactive physics chemistry unstable oxidizable activated
Similar spelling:   restive
  reactivate
  restively
  rectifier
  rectified
  reactivity
  restiveness
  rectifiable
  Restivo
  rectify