Polynesian multihull terminology, such as "ama", "aka" and "vaka" (or "waka") aremultihull terms that have been widely adopted beyond the South Pacific where these terms originated. This Polynesian terminology is in common use in the Americas and the Pacific but is almost unknown in Europe, where the English terms "hull" and "outrigger" form normal parlance. Outriggers,catamarans, andoutrigger boats are a common heritage of allAustronesian peoples and predate theMicronesian andPolynesian expansion into the Pacific. They are also the dominant forms of traditional ships inIsland Southeast Asian andMalagasy Austronesian cultures, where local terms are used.[1][2]
The termvaka orwaka means "boat" or "canoe" in most Polynesian languages. It comes fromProto-Austronesian *abaŋ, meaning "ship" or "canoe".Cognates in other Austronesian languages includeIvatanAwang,Tagalog andVisayanbangka,Malaywangkang, andFijianwaqa.[3]
The termama is a word in thePolynesian andMicronesian languages to describe theoutrigger part of acanoe to provide stability. Today, among the various Polynesian countries, the wordama is often used together with the wordvaka (Cook Islands) orwaka (Māori) orva'a (Samoa Islands,Tahiti), cognate words in various Polynesian languages to describe a canoe.
ThePolynesian termvaka is the mainhull, theama is the outrigger, and theaka oriako (Hawaiian) is the support connecting the two (not three) hulls. The termama andaka have been widely applied to moderntrimarans.
In modern sailing, the term is sometimes used to refer to the outrigger on double-outrigger canoes (trimarans), or the two sections of acatamaran. However, calling the two sections of a catamaran by the word ama is not technically correct since they are of equal size. A catamaran is technically a wa'a wa'a or double canoe connected by anaka.[4]
On a proa, the ama may provide lift orballast, depending on whether it is designed to be used toleeward orwindward; on a trimaran it is designed primarily to provide lift. There are many shapes of ama; those used inproas are generally laterally symmetric, as the proa is designed to sail with either end forwards, whiletrimaran ama are one-directional and may have no axis of symmetry.
The most advanced ama are composed of highly curved surfaces that generatelift when driven forward through the water, much like anairplane wing. This lift may be directed to the windward, used to counter slipping toleeward, or may be oriented vertically to counterheeling forces from thesailing rig. These highly curved structures are much more difficult to manufacture than traditional ama and are therefore more expensive. TheBruce foil is an example of a type ofleeboard often attached to an ama to assist in producing lift.
Even though double-outrigger ships (trimarans, sometimes informally referred to as "proas" historically) of other relatedAustronesian groups inIsland Southeast Asia,Island Melanesia, andMadagascar didn't reach Polynesia or Micronesia, they may also sometimes use Polynesian terminology in modern times, especially when used in sport sailing.[5]
The US Navy tri-hullIndependence-class littoral combat ship refers to their outboard hull sections as an "Amah". "An Amah tip is the leading edge of the all-aluminum, trimaran-type vessel’s outrigger, or amah, and is more than seven feet across and weighs 850 pounds."[6]
