lack lack /ˈlæk/

noun

1. () The state of needing something that is absent or unavailable  ( want , deficiency , lack )
   the state of needing something that is absent or unavailable
    There is a serious lack of insight into the problem
   there is a serious lack of insight into the problem
    Water is the critical deficiency in desert regions
   water is the critical deficiency in desert regions
    For want of a nail the shoe was lost
   for want of a nail the shoe was lost
   

verb

1. () Be without  ( miss , lack )
   be without
    This soup lacks salt
   This soup lacks salt
    There is something missing in my jewelry box!
   There is something missing in my jewelry box!