Search Result for "reactive": 
Wordnet 3.0

ADJECTIVE (2)

1. participating readily in reactions;
- Example: "sodium is a reactive metal"
- Example: "free radicals are very reactive"

2. reacting to a stimulus;
- Example: "the skin of old persons is less reactive than that of younger persons"
[syn: reactive, responsive]



The Collaborative International Dictionary of English v.0.48:

Reactive \Re*act"ive\ (r[-e]*[a^]kt"[i^]v), a. [Cf. F.
   r['e]actif.]
   Having power to react; tending to reaction; of the nature of
   reaction. -- Re*act"ive*ly, adv. -- Re*act"ive*ness, n.
   [1913 Webster]


WordNet (r) 3.0 (2006):

reactive
    adj 1: participating readily in reactions; "sodium is a reactive
           metal"; "free radicals are very reactive" [ant:
           unreactive]
    2: reacting to a stimulus; "the skin of old persons is less
       reactive than that of younger persons" [syn: reactive,
       responsive]