abri
approach trench
aqueduct
bunker
canal
canalization
channel
communication trench
confirmation
countermine
coupure
crimp
cut
deep-rootedness
deep-seatedness
dike
ditch
double sap
dugout
embedment
encroachment
entrance
establishment
fire trench
fixation
fixedness
fixity
fixture
flying sap
fortified tunnel
fosse
foxhole
gallery
goffer
gutter
ha-ha
impingement
implantation
imposition
incursion
infiltration
infixion
influx
infringement
injection
inroad
insinuation
interference
interjection
interloping
fortification
munition
retrenchment
boyau
breastwork
go-round
hornwork
intrench
intrenchment
matriarchate
rail fence
scrapheap
shortlist
tool-making