A closed circuit designed to be used as an antenna. It consists of one or more turns of wire lying in the same or parallel planes. The frequency of operation or the method of excitation is normally such as to give a substantially uniform current distribution along the conductor.
Reference: B.S. (modified)
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
Centre of buoyancy
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM