reactive

Definition of Reactive in English :

1. reactive

participating readily in reactions

Example Sentences:
'sodium is a reactive metal'
'free radicals are very reactive'

2. reactive, responsive

reacting to a stimulus

Example Sentences:
'the skin of old persons is less reactive than that of younger persons'

WordNet Lexical Database for English. Princeton University. 2010.

Reactive

adjective

1.

readily partaking in chemical reactions

sodium is a reactive metal

free radicals are very reactive

2.

of, concerned with, or having a reactance

3.

responsive to stimulus

4.

(of mental illnesses) precipitated by an external cause

reactive depression

5.

(esp of a business or organization) tending to react to events rather than initiate change

adjective

1.

tending to react

2.

of, caused by, or showing reaction or reactance

adj.

1. Tending to be responsive or to react to a stimulus.

2. Characterized by reaction.

3. Chemistry & Physics Tending to participate readily in reactions.