WordWeb Online

1. Without good reason
   "one cannot say such things lightly"
    
2. With few burdens
   "experienced travellers travel lightly";
   - light
    
3. With little weight or force
   "she kissed him lightly on the forehead";
   - softly, gently
    
4. Indulging with temperance
   "we eat lightly in the morning"
    
5. With indifference or without dejection
   "he took it lightly"
    
6. In a small quantity or extent
   "apply paint lightly";
   - thinly
    
7. To a slight degree
   "her speech is only lightly accented"

Antonym: hard