Semi-submersible may refer to a self-propelled vessel, such as:
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Heavy-lift ship, which partially submerge to allow their cargo (another ship) to float into place for transport
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Narco-submarine, some of which remained partially on the surface
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Semi-submarine, which cannot fully submerge
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Semi-submersible naval vessel
A semi-submersible naval vessel is a hybrid warship, that combines the properties of a surface ship and submarine by using water ballast to partially immerse and minimize its above-waterline profile, thereby improving its stealth characteristics ...
, which partially submerges to minimize being observed
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Semi-submersible platform
A semi-submersible platform is a specialised marine vessel used in offshore roles including as offshore drilling rigs, safety vessels, oil production platforms, and heavy lift cranes. They have good ship stability and seakeeping, better than ...
, which is typically transported to a location where it is placed in service
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Oil platform, a large structure with facilities for well drilling to explore, extract, store, and process petroleum and natural gas, in deeper water (more than 1,500 metres (4,900 ft)), the semisubmersibles or drillships are maintained at the required drilling location using dynamic positioning.
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Boat types
Nautical terminology
Submarines by type