bulkhead

American  

[buhlk-hed] / ˈbʌlkˌhɛd /

noun

1. Nautical. any of various wall-like constructions inside a vessel, as for forming watertight compartments, subdividing space, or strengthening the structure.

2. Aeronautics. a transverse partition or reinforcing frame in the body of an airplane.

3. Civil Engineering.

   1. a partition built in a subterranean passage to prevent the passage of air, water, or mud.

   2. a retaining structure of timber, steel, or reinforced concrete, used for shore protection and in harbor works.

4. Building Trades.

   1. a horizontal or inclined outside door over a stairway leading to a cellar.

   2. a boxlike structure, as on a roof, covering a stairwell or other opening.

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bulkhead British  

/ ˈbʌlkˌhɛd /

noun

1. any upright wall-like partition in a ship, aircraft, vehicle, etc

2. a wall or partition built to hold back earth, fire, water, etc

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Other Word Forms

• bulkheaded adjective

Etymology

Origin of bulkhead

First recorded in 1490–1500; bulk ² + head

Explanation

The divider or wall between sections of a plane or large ship is called a bulkhead. When you're seated in first class on a jet, there's a bulkhead between you and the pilot's cabin. The bulkhead you're most likely to see is in a commercial airliner, dividing the flight crew from the passengers and sometimes the first class flyers from those in coach. Other vehicles have them too, including submarines and ships — these bulkheads help strengthen the vessels and keep different areas watertight. The Old Norse root of bulkhead is bálkr, "partition."

Example Sentences

For outdoor adventure enthusiasts, there is also a new dock with concrete pilings, boat and jet ski lifts, and vinyl bulkhead that are situated on a 75 x 160 waterfront lot.

From MarketWatch • Feb. 12, 2026

He learned to never sit near the bulkhead where bassinets frequently were placed.

From The Wall Street Journal • Jan. 30, 2026

A judge-led commission later found "a litany of errors" related to the Lamma IV, including a missing bulkhead door which contributed to the ferry sinking within two minutes.

From Barron's • Jan. 21, 2026

But to the naked eye, they had the charm of a bulkhead door leading to a scary basement.

From New York Times • Apr. 1, 2024

“All right,” says Carlyle, leaning back against the green copper bulkhead of the map room.

From "Challenger Deep" by Neal Shusterman