Wordnet 3.0
NOUN (1)
1. 
 a very short time (as the time it takes the eye to blink or the heart to beat); 
- Example: "if I had the chance I'd do it in a flash"[syn: blink of an eye, flash, heartbeat, instant, jiffy, split second, trice, twinkling, wink, New York minute]
WordNet (r) 3.0 (2006):
blink of an eye
    n 1: a very short time (as the time it takes the eye to blink or
         the heart to beat); "if I had the chance I'd do it in a
         flash" [syn: blink of an eye, flash, heartbeat,
         instant, jiffy, split second, trice, twinkling,
         wink, New York minute]