Wordnet 3.0
ADJECTIVE (1)
1. 
 subjected to intensive forced indoctrination resulting in the rejection of old beliefs and acceptance of new ones; 
- Example: "brainwashed prisoners of war"- Example: "captive audiences for TV commercials can become brainwashed consumers"
The Collaborative International Dictionary of English v.0.48:
brainwashed \brainwashed\ adj.
   subjected to intensive forced indoctrination resulting in the
   rejection of old beliefs and acceptance of new ones.
   brainwashed prisoners of war; captive audiences for TV
   commercials can become brainwashed consumers unbrainwashed
   [WordNet 1.5]
WordNet (r) 3.0 (2006):
brainwashed
    adj 1: subjected to intensive forced indoctrination resulting in
           the rejection of old beliefs and acceptance of new ones;
           "brainwashed prisoners of war"; "captive audiences for TV
           commercials can become brainwashed consumers" [ant:
           unbrainwashed]