reserve buoyancy: meaning, definition, pronunciation and examples

No, they are related but distinct. Freeboard is the physical distance from the waterline to the main deck. Reserve buoyancy is the *volume* of the watertight hull above the waterline, which provides the actual upward force (buoyancy) if the ship submerges further.

Only metaphorically. In business or project management, one might speak of 'reserve buoyancy' to mean a financial or resource safety margin, but this is a creative extension, not the standard meaning.

If a ship loses its reserve buoyancy (e.g., through hull damage, flooding, or being overloaded), it loses its safety margin. It will sink lower in the water, become less stable, and is at imminent risk of foundering or being swamped by waves.

It is typically expressed as a weight (e.g., in tonnes), representing the weight of water that would fill the watertight volume above the waterline. It is a key figure in a ship's stability calculations and documentation.

The potential buoyancy of a ship or boat that remains above the waterline, providing a margin of safety against swamping or sinking.

Reserve buoyancy is usually technical, nautical in register.

Reserve buoyancy: in British English it is pronounced /rɪˈzɜːv ˈbɔɪ.ən.si/, and in American English it is pronounced /rɪˈzɝːv ˈbɔɪ.ən.si/ or /ˈbuː.jən.si/. Tap the audio buttons above to hear it.