types:
barricade
a barrier (usually thrown up hastily) to impede the advance of an enemy
bulwark
a fencelike structure around a ship's deck (usually plural)
crash barrier
a strong protective barrier that is erected around a racetrack or in the middle of a dual-lane highway in order to reduce the likelihood of severe accidents
dam,
dike,
dyke
a barrier constructed to contain the flow of water or to keep out the sea
fender,
wing
a barrier that surrounds the wheels of a vehicle to block splashing water or mud
grate,
grating
a barrier that has parallel or crossed bars blocking a passage but admitting air
hurdle
a light movable barrier that competitors must leap over in certain races
rail,
railing
a barrier consisting of a horizontal bar and supports
barricade,
roadblock
a barrier set up by police to stop traffic on a street or road in order to catch a fugitive or inspect traffic etc.
backstop
(baseball) a fence or screen (as behind home plate) to prevent the ball from traveling out of the playing field
bar
(law) a railing that encloses the part of the courtroom where the judges and lawyers sit and the case is tried
chicane
a movable barrier used in motor racing; sometimes placed before a dangerous corner to reduce speed as cars pass in single file
door
a swinging or sliding barrier that will close the entrance to a room or building or vehicle
fife rail
the railing surrounding the mast of a sailing vessel
gate
a movable barrier in a fence or wall
hatch
a movable barrier covering a hatchway
hedge,
hedgerow
a fence formed by a row of closely planted shrubs or bushes
milldam
dam to make a millpond to provide power for a water mill
rail fence
a fence (usually made of split logs laid across each other at an angle)
stone wall
a fence built of rough stones; used to separate fields
taffrail
the railing around the stern of a ship
wall
a masonry fence (as around an estate or garden)
weir
a low dam built across a stream to raise its level or divert its flow
weir
a fence or wattle built across a stream to catch or retain fish