Abdomen: the belly region of a vertebrate animal, or the hind segment of the body of an insect, crustacean or other arthropod.
Abiotic: Non-living (physical and chemical parts) that affect a marine organism's life. For example salinity, temperature, oxygen or pressure.
Aboard: On board a vessel at sea.
Abyss: The deep sea environment between 4000 & 6000 m.
Abyssal plain: the flattened floor of the deep ocean offshore from the continental margin.
Abyssal zone: the deep sea region below 13,000 feet (4,000 meters).
Acclimatisation: The process of gradually introducing a newly acquired fish or invertebrate to its aquarium. Process where anemone fish gradually gets used to nematocysts of anemone.
Acids: Compounds which have a pH value below 7. Compounds that dissociate in water to form H+ ions.
Acrylic: Very hard form of plastic used in boat parts and aquariums.
Adaptation: a characteristic body part, shape or behavior that helps a plant or animal survive in its environment.
Adult stage: The mature stage of an organism which is capable of reproduction.
Aeration: A process of maintaining the oxygen level of the water by pushing air bubbles up through it.
Aerobic: containing oxygen or requiring oxygen.
Aft: Toward the stern or rear part of a boat.
Aggressors: Animals which attack other animals for food or for the defence of their territory.
Ahead: In a forward direction or in the front of the boat.
Airway: Refers to the tube that connects the mouth to the lungs - the pharynx and bronchi.
Albatross: a large seabird that spends much of its life wandering over the open ocean far from land.
Algae: a large group of primitive plants that live mostly in water. Kelp and other seaweeds are algae. Algae have simple bodies--many kinds exist as single cells.
Algal blooms: An increase in the concentration of phytoplankton. Sometimes caused by excess nutrients.
Algin: a slippery substance extracted from brown algae, including kelp. Algin is used in paint, toothpaste, ice cream and many other products because it thickens liquids and binds oily and watery liquids together.
Alkaline: Substance with pH between 814.
Alternation of generations: A life cycle in which the generation alternates from sexual to asexual (occurs for example, in sea lettuce).
Amateurs: Refers to people who fish for recreation and who do not sell their fish.
Amphipods: small, prawn like crustaceans.
Anaerobic: not containing oxygen or not requiring oxygen.
Anaesthetic: Substance used to reduce pain in an area by controlling nerve endings.
Anchovies: small silvery fishes that swim in big schools. Anchovies are eaten by tuna, salmon, penguins, and many other predators.
Anemometer: An instrument used to measure wind speed.
Anemone: a sea animal with a crown of stinging tentacles at the top of a fleshy stalk. Often called a "sea anemone."
Anglers: Fishing term for amateur fishers who fish with rod and line.
Angling device: a modified dorsal fin or chin barbel on some deep sea fishes that acts like a rod and bait to attract prey or mates.
Anoxic: without oxygen.
Antarctic convergence: Distinct region where the warmer, northern waters sink below cold Antarctic currents.
Antenna: a long, slender organ or feeler located on the head of an insect, crustacean or other arthropod; or any long, slender rod used for gathering or transmitting information.
Anti-fouling chemicals: Chemicals which slow down the process of attachment of marine animals, e.g. paints which stop barnacles growing on the hull of a ship.
Antibiotics: Chemicals that stop the growth of bacteria.
Antivenene: Drug used to combat specific marine venom, e.g. stonefish antivenene.
Appendages: Attached part of a limb of an animal, e.g. the leg of crayfish is an appendage.
AQIS: Australian Quarantine Inspection Service.
Aquaculture: Cultivation of fish, molluscs and other aquatic organisms in fresh or salt water for sale for food for humans.
Aquarium: Pond or tank in which living plants and animals are kept away from their natural habitat.
Aquatic: of the water; living in the water.
Armour: Outer covering of organism used for protection
Arthropod: a large group of invertebrate animals with jointed legs, including the insects, scorpions, crustaceans and spiders.
Artefacts: Items found on shipwrecks.
Astern: In a backward direction; behind the boat.
Atmosphere: Gaseous fluid surrounding the Earth.
Atmospheric pressure: the pressure of the air here on the earth's surface. At sea level, atmospheric pressure equals 14.7 pounds per square inch (2.6 kilograms per square centimeter). This amount of pressure is known to scientists as one atmosphere. People and other land animals are adapted to one atmosphere of pressure and thrive on the earth's surface. But water is much heavier than air, and as we dive into the ocean, pressure increases. Divers feel an extra atmosphere's worth of pressure with every 33 foot (10 meter) increase in depth.
Atoll: a ring-shaped coral reef that forms around a volcanic island.
Aviary: an enclosure where birds can fly around freely.
Avocet: a shorebird with long legs and a very long, upward-curving bill.