Wordnet 3.0
VERB (1)
1. 
 die before; 
 die earlier than; 
- Example: "She predeceased her husband"
The Collaborative International Dictionary of English v.0.48:
Predecease \Pre`de*cease\, v. t.
   To die sooner than. "If children predecease progenitors."
   --Shak.
   [1913 Webster]
The Collaborative International Dictionary of English v.0.48:
Predecease \Pre"de*cease`\, n.
   The death of one person or thing before another. [R.]
   --Brougham.
   [1913 Webster]
WordNet (r) 3.0 (2006):
predecease
    v 1: die before; die earlier than; "She predeceased her husband"