reactive

re·ac·tive

adj \rē-ˈak-tiv\

Definition of REACTIVE

1

a : of, relating to, or marked by reaction <reactive symptoms> <a reactive process> b : capable of reacting chemically <highly reactive materials>

2

a : readily responsive to a stimulus <the skin of the geriatric is less reactive than that of younger persons—Louis Tuft> b : occurring as a result of stress or emotional upset especially from factors outside the organism <reactive depression>