scupper

nouns

drain that allows water on the deck of a vessel to flow overboard
scupper
is a type of (narrower)
a pipe through which liquid is carried away
drain, drainpipe, waste pipe

verbs

wait in hiding to attack
ambuscade, ambush, bushwhack, lie in wait, lurk, scupper, waylay
put in a dangerous, disadvantageous, or difficult position
endanger, expose, peril, queer, scupper