The Collaborative International Dictionary of English v.0.48:

Standstill \Stand"still`\ (-st[i^]l`), n.
   A standing without moving forward or backward; a stop; a
   state of rest.
   [1913 Webster]

WordNet (r) 3.0 (2006):

standstill
    n 1: a situation in which no progress can be made or no
         advancement is possible; "reached an impasse on the
         negotiations" [syn: deadlock, dead end, impasse,
         stalemate, standstill]
    2: an interruption of normal activity [syn: stand,
       standstill, tie-up]