WordWeb Online

1. In an unfortunate way
   "sadly he died before he could see his grandchild"
   - unhappily
    
2. With sadness; in a sad manner
   "'She died last night,' he said sadly"
    
3. In an unfortunate or deplorable manner
   "he was sadly neglected"
   - deplorably, lamentably, woefully

See also: sad

Antonym: happily

Encyclopedia: Sadly