1. 
[syn: nerve-racking, nerve-wracking, stressful, trying]
The Collaborative International Dictionary of English v.0.48:
nerve-racking \nerve-racking\ (n[~e]rv"-r[a^]k`[i^]ng), adj.
   Extremely irritating to the nerves; stressful; trying; as,
   nerve-wracking noise. [Also spelled nerve-wracking.]
   Syn: stressful, trying.
        [WordNet 1.5]
WordNet (r) 3.0 (2006):
nerve-racking
    adj 1: extremely irritating to the nerves; "nerve-racking
           noise"; "the stressful days before a war"; "a trying day
           at the office" [syn: nerve-racking, nerve-wracking,
           stressful, trying]