outage

outage
    n 1: the amount of something (as whiskey or oil) lost in storage
         or transportation
    2: a temporary suspension of operation (as of computers); "there
       will be a network outage from 8 to 10 a.m."
    

19 Moby Thesaurus words for "outage":
      arrearage, break, defalcation, defect, deficiency, deficit,
      discontinuity, gap, hiatus, interval, lack, lacuna, missing link,
      need, omission, shortage, ullage, want, wantage