Wordnet 3.0
ADJECTIVE (1)
1. 
 causing loss of physical or intellectual bearings; 
- Example: "making so many turns to the right and then the left was completely disorienting"- Example: "a sharp blow to the head can be disorienting"
The Collaborative International Dictionary of English v.0.48:
disorienting \disorienting\ adj.
   1. causing disorientation: causing confusion of directions.
      Also See: unoriented. Antonym: orienting
      [WordNet 1.5 +PJC]
WordNet (r) 3.0 (2006):
disorienting
    adj 1: causing loss of physical or intellectual bearings;
           "making so many turns to the right and then the left was
           completely disorienting"; "a sharp blow to the head can
           be disorienting" [ant: orientating, orienting]