Source : Webster's Revised Unabridged Dictionary (1913)

Predecease \Pre`de*cease\, v. t.
   To die sooner than. ``If children predecease progenitors.''
   --Shak.

Predecease \Pre"de*cease`\, n.
   The death of one person or thing before another. [R.]
   --Brougham.

Source : WordNet®

predecease
     v : die before; die earlier than; "She predeceased her husband"