Ama (sailing)

The term ama is a word in the Polynesian and Micronesian languages to describe the outrigger part of a canoe to provide stability. Today, among the various Polynesian countries, the word ama is often used together with the word vaka (Cook Islands) or waka (Māori) or va'a (Samoa Islands, Tahiti), cognate words in various Polynesian languages to describe a canoe.

In modern sailing, the term is sometimes used to refer to the outrigger on a proa or trimaran, or the two sections of a catamaran. 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 an aka.

The Polynesian term vaka is the main hull, the ama is the outrigger, and the aka or iako (Hawaiian) is the support connecting the two (not three) hulls. The term ama and aka have been widely applied to modern trimarans.

On a proa, the ama may provide lift or ballast, depending on whether it is designed to be used to leeward or windward; on a trimaran it is designed primarily to provide lift. There are many shapes of ama; those used in proas are generally laterally symmetric, as the proa is designed to sail with either end forwards, while trimaran ama are one-directional and may have no axis of symmetry.

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