1. a change from a financially rewarding but stressful career to a less well paid but more fulfilling one;
2. a change to a lower gear in a car or bicycle;
WordNet (r) 3.0 (2006):
downshift
n 1: a change from a financially rewarding but stressful career
to a less well paid but more fulfilling one
2: a change to a lower gear in a car or bicycle