WordNet (r) 3.0 (2006):

lie in wait
    v 1: wait in hiding to attack [syn: ambush, scupper,
         bushwhack, waylay, lurk, ambuscade, lie in wait]

Moby Thesaurus II by Grady Ward, 1.0:

36 Moby Thesaurus words for "lie in wait":
   abide, ambuscade, ambush, await, bide, couch, creep, gumshoe,
   lay for, lay wait, lay wait for, lie in ambush, lurk, mark time,
   nightwalk, prowl, pussyfoot, shadow, sit up for, skulk, slink,
   sneak, stalk, stay up for, steal, sweat, sweat it out, sweat out,
   tiptoe, wait, wait for, wait on, wait up for, watch,
   watch and wait, waylay