[1] : The Collaborative International Dictionary of English v.0.48

sustainment \sustain"ment\, n.
   the act of sustaining; maintenance; support. --milton.
   lowell.
   1913 webster

[2] : WordNet (r) 2.0

sustainment
     n : the act of sustaining life by food or providing a means of
         subsistence; "they were in want of sustenance"; "fishing
         was their main sustainment" syn: sustenance, sustentation,
          maintenance, upkeep
see also:
sustenance sustentation maintenance upkeep 

Sustainment >> S Words
Sustainment, definition of term: Sustainment
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