bulkhead

noun

1. 1.A vertical partition dividing the hull into separate compartments; often made watertight to prevent excessive flooding if the ship's hull is breached.
2. 2.A similar partition in an aircraft or spacecraft.
3. 3.Mechanically, a partition or panel through which connectors pass, or a connector designed to pass through a partition.
4. 4.A pressure-resistant sealed barrier to any fluid in a large structure.
5. 5.A retaining wall along a waterfront.