This article is a dictionary of sorts of common terms used whether slang or professional among catamaran sailors.
balsa cored (adj.) – description of a type of building technique common on catamaran used for weight saving purposes. End grain balsa is sandwiched between two layers of fiberglass to stiffen, lighten, and insulate the hull and deck of many catamarans. Usually balsa coring is discussed in terms of concerns about water logged or “wet” coring material which is a significant expensive as well as a common issue especially as catamarans get older.
beach platform (n.) – a type of platform at the back of catamaran in particular the Voyage 440. The platform runs the whole back width between the swim platforms and function as a place behind the cockpit combing to layout, fish, and dangle your feet.
beachable (adj.) – describing a class of catamaran which can safely be run aground and mooring on a sandy bottom often a beach. The hull is constructed so that the design can stay upright and support its own weight when the tide goes out.

breakaway skeg (n.) – an underwater appendage of some catamarans including some Leopard and Outremer models which protects the rudders and breaks away in the case of an impact whether in a grounding situation or underwater debris.
bridge clearance (n.) – also known as air draft. The height from the water level to the tip of the mast. Should include the height all the way to the tip most antenna. Heights provided by manufacturers often underestimate because of the antenna. A key number is 65 feet which in the United States is the limiting clearance for fixed bridges on the Intracoastal waterway. Some owners cut down their masts to get under this limit. Many manufacturers specifically design around the 65 foot limit although with catamarans this is difficult as they tend to have taller masts than other sailboats and smaller headsails for the same waterline length.
bridgedeck clearance (n.) – distance between the center section of catamaran where salon is aka the bridgedeck and the water. Common focus is if the catamaran “slaps” which means in rough seas waves come up and pound against the bottom of the hull. Higher bridgedeck clearance is preferred and considered a bluewater characteristic while low bridgedeck clearance is a common concern. A good way to measure is by extending a measuring tape from behind the cockpit to the waterline and a normal rule of thumb number is two feet.
charter version (adj.) – catamaran built for the charter trade usually Moorings or Dream Yacht Charters which has additional cabins and heads. Usually this means four cabins and four heads. This layout is ideal for charter but often private owners prefer a more luxurious master hull giving them a three cabin and two head layout.
companionway (n.) – the main opening to access the interior of the catamaran. This may be a single hatch like door for example on Mantas or large sliding doors which fold up above the cockpit like on Seawind catamarans. A key design interest for builders and owners is the connection and flow between the cockpit where the most time is spent while onboard and the galley and salon areas.
condomaran (n.) – derogative term towards space focused, performance challenged catamarans such as a Lagoon, Leopard, or Fountaine Pajot.
cored above waterline (adj.) – a description of a common build technique where to lessen water intrusion into balsa coring, that sandwich is not carried below the water line. The term is a bit deceptive as usually the coring does go farther than what most owners would think and often below the waterline although not all the way to the bottom of the hull.
crew quarters (n.) – a pretty minimal and harsh accommodations area on catamarans forward in a bow where the captain and crew are supposed to sleep and live when a catamaran is captain chartered. Often on used catamarans becomes an excellent storage area. An unlivable marvel of a cabin that is suggestive of suffering.
cross beam (n.) – beam usually metal that is forward most and the headsail attaches to. Keeps the two hulls structurally joined at the bow.
cutter (adj.) – a rare type of sailboat where there are two headsails and the mast is well aft. Easily confused with a cutter rigged sloop. See definition for sloop cutter.
daggerboards (n.) – boards used to help windward performance and common on performance catamarans like Catanas while not used on charter catamarans like Lagoons and Leopards. Helps the catamaran head further upwind and make less leeway.

davits (n.) – a critical item on a catamaran which holds and supports the dinghy behind the cockpit. Many different arrangements are common. The davits are operated using a line or multiple lines to lower the dinghy into and raise out of the water for security from getting stolen at anchor or for safety offshore. A common concern of the ocean going sailor is monitoring and making sure if rough seas that the dinghy is tight and secure.
emergency hatch (n.) – a hatch at the bottom of the boat usually under the salon or steps downward into one of the hulls which becomes an emergency escape hatch if the catamaran flips and goes turtle. Required safety feature that hopefully no sailor needs to use. Also can be used to fish from in calm water. Can be a source of leaks or come dangerously loose and cause drama offshore.
family version (n.) – a charter layout of a used catamaran that is preferable for families that usually want at least four cabins to accommodate three or more children. The best type of catamaran!
flat top sail (n.) – a high tech fancy sail with a flat top. Expensive and not as common although becoming more common. Maximizes sail area.
flybridge (n.) – helm above the cockpit common on some popular charter catamarans like the Lagoon 440 or Lagoon 50. Design allows great visibility from aloft but also roughly exposes the captain and can uncomfortably separate the owner-captain from his friends and family.
flying ahull (n.) – when one hull lifts off the water and a catamaran sails only with one hull in the water. Not a good sign for almost any catamaran even performance catamaran. Likely followed by flipping and mayday on cruising catamarans.
four heads (n.) – number of heads on many catamaran layouts preferred for charter. Each guest has a cabin and head, so that no one must share heads during their week together. Usually a negative for private ownership even for families that prefer four cabins as more heads means more problems and less space for other accommodations.
french built (adj.) – denotes the catamaran was built in France. Suggests a more performance focus like Catana or lighter production built like Lagoon. Definitely an aesthetic focus on fast striking lines.
forward cockpit (adj.) – a cockpit in front of the salon area usually accessed by a forward facing companionway door. Made famous by the Leopard 44. Some sailors question usefulness or durability in heavy seas of a large opening on the front side of a catamaran.

galley down (adj.) – kitchen area down in one of the hulls. Associated with older designs or designs seeking weight advantage of lower center of gravity such as Antares 44. Uncommon in more recent catamarans and unheard of for charter catamarans as galley down is inconvenient for four guests for sleeping an food access.
galley up (adj.) – Common for most modern catamarans. Improves flow from cockpit and helm to kitchen as well as separation of shared living areas from private cabin areas.
hard top (adj.) – solid glass top to protect guests in cockpit from sun exposure as well as give a platform above for sail handling or diving from into water. Also a sunbathing area or area for solar panels.
ICW friendly (adj.) – catamaran with rig height below 65 feet to go under fixed bridges along United States eastern seaboard.
IO drive (n.) – a rare engine and drive combination as seen on Gemini 105 MC catamarans where a single diesel engine is centerline and there is an outdrive mounted on a hinged support.
ketch (adj.) – very unusual rig configuration on a catamaran with two masts and the second mast aka mizzen mast being shorter than the main forward mast.
outboard (n.) – gas engine that mounts to a stern or inside a swim platform and includes both the motor and drive. Less expensive and easier to replace yet less durable and less safe offshore. Common on smaller catamarans under 40 feet. Can come in twin configurations or a single centerline configuration. Also a separate small horsepower outboard is usually the power for the dinghy.
owner version (adj.) – usually less common version of a production catamaran where the layout is optimized for private use not charter. These models were usually never chartered and command a premium price on the used market both because of the lower wear from private ownership and the more comfortable layout. Typically in the 40 foot range which consists of the majortiy of catamarans, this means three cabins and two heads with one hull using the missing cabin and head space for a larger head and cabin and maybe an office or lounge area.
performance catamaran (n.) – catamaran with daggerboards which is geared towards more minimal accommodations and faster, lighter performance with a more athletic crew. Rarely chartered.
production catamaran (n.) – charter type catamarans with a focus on space and cabins and low prices. Large numbers built and send to Caribbean to be bareboated for 5 years.
raked mast (n.) – a mast tilted backwards common on catamarans as compromise between performance and accommodations. Dean catamarans are a common brand known for noticeable rake.

saildrive (n.) – a type of drive common on most newer catamarans which helps maximize space and minimize drag as well as being cheaper to build. The engines are in lockers in the swim platforms instead of under the aft berths. There are maintenance issues such as increased difficulty in changing oil and underwater seals which commonly deteriorate and let raw water into and emulsify the oil.
salon (n.) – area inside the catamaran above the bridgedeck which is usually common area of inside helm, large lounge and settee, galley on galley up designs.
sloop (n.) – the most common sail arrangement which consists of a large mainsail and single headsail. The mast is well forward at the front of the salon.
sloop cutter (n.) – a less common sail arrangement of a sloop with the mast forward but two headsails.
snubber (n.) – a rope tied between the two hulls at the bow which hangs downward and has a shackle which is hooked into the anchor chain to take the load of the anchor off the windlass when deployed.
solid foredeck (n.) – a type of design where instead of tramplolines the deck is composed of solid glass. Weight is a concern and this arrangement is less common normally seen on Privileges. Allows for a more solid lounge area and additional storage on deck.
solid glass (n.) – referring to a type of catamarans usually older which does not have coring material in either the hull or deck or both. Weight is an issue and this type of catamaran is slower but the solid glass makes it also impenetrable to water intrusion a common and expensive problem on most catamarans. Examples include Catalac or PDQ catamarans.
south african built (adj.) describing a catamaran built in the second most common exporting country. These catamarans are tended to be though of as stronger and more bluewater capable than French built catamarans. Most common example is Robertson & Caine’s Leopard line of catamarans which are sold mostly to Moorings for charter.
stem (n.) – leading tips of the hulls. Often get banged up from running into things and have gelcoat and paint repairs.
tiller (n.) – a type of steering system where a long piece of wood or carbon fiber is attached directly to the rudder. Outremer is an example of a catamarans with tillers. Typically these are performance oriented catamarans and the tiller allows the helmsperson better feel of the sailing performance. The helm positioning also exposes the driver more to the elements.
trampolines (n.) – nets that are used to finish out the bow area and conserve weight on most catamarans. These are important to keep in good condition for safety reasons. Make a great lounge area and in rough seas a fun spray pad.
two heads (n.) – catamaran that either is a three or four cabin version. Some charter built versions still maintain two heads and guests in each hull must share the head.
vertical windows (n.) – windows made famous by Lagoon catamarans. These are windows around the salon that make it very light and airy and allow a higher cabin top with more headroom. The downside is more windage which affects maneuverability when in close quarters and general sailing performance.