no-go

from WordNet (r) 3.0 (2006)

no-go
    adj 1: not functioning properly or in suitable condition for
           proceeding; "the space launch was no-go" [ant: {go}]

from The Collaborative International Dictionary of English v.0.48

no-go \no-go\ adj.
   not functioning properly or in suitable condition for
   proceeding; as, the space launch was no-go. Opposite of {go},
   a.
   [WordNet 1.5]