Main Entry: re·ac·tive

Pronunciation: \rē-ˈak-tiv\

Function: adjective

Date: 1794

1 : of, relating to, or marked by reaction or reactance
2 a : readily responsive to a stimulus b : occurring as a result of stress or emotional upset <reactive depression>

— re·ac·tive·ly adverb

— re·ac·tive·ness noun

— re·ac·tiv·i·ty \(ˌ)rē-ˌak-ˈti-və-tē\ noun