arrest
barb
barbed
barblock
barbwire
barrier
bondage
border
boundary
bundle
cage
captivity
clew
coil
confinement
crime
danger
dangerous
detention
gaol
hank
illustration
imprisonment
iron
isolation
jail
limitation
loop
metal
prevention
prickle
prison
protection
protective
reel
restriction
roll
safety
security
skein
spike
steel
tangle
thorn
truss
twist
warning
wire