Key terms & definitions

An engineered channel or system that carries water from its source to where it is needed.

Dissolved in water; shown by the state symbol $(aq)$.

Dissolved in water; shown by the state symbol (aq) in a chemical equation.

A solution in which an acid is dissolved in water and can provide hydrogen ions, H⁺.

A solution in which a substance is dissolved in water, represented by the state symbol $(aq)$.

A solution in which water is the solvent.

A solvent in which water is the solvent or main solvent.

A solvent in which water is the solvent or a main part of the solvent mixture.

A layer of permeable rock that stores and allows the movement of groundwater.

An underground layer of permeable rock that holds water.

The eagle standard of a Roman legion, representing its identity and honour.

An association of Arab states that sought cooperation and coordinated policies, including their response to Israel.

Farming that produces crops rather than primarily raising animals.

The growing of crops, rather than the rearing of livestock.

Land suitable for growing crops.

A wave of protests and uprisings across North Africa and the Middle East beginning in late 2010, including demands for democracy and an end to authoritarian rule.

A person who has attained enlightenment and nibbana by following the Buddha's teaching; the ideal especially emphasised in Theravada Buddhism. Also called an arhat.

The ‘Greatest Altar’ associated with Hercules’ worship at Rome; the Cacus story explains why the community established this worship.

A ceremony in which a lighted lamp is offered before a deity and worshippers receive its blessing.

Government in which a ruler exercises power without effective legal or parliamentary restraint.

The exercise of authority according to a ruler’s personal wishes rather than fair, consistent rules or accepted customs.

The exercise of power according to a ruler's wishes rather than consistent laws and fair procedures.

Settling a dispute by referring it to an independent third party for a decision rather than using force.

Using people outside a dispute to help resolve it; Qur’an 4:35 calls for a representative from each spouse’s family.

A process in which the parties agree to let an independent person or body consider the evidence and make a decision that is usually legally binding.

A part of a circle's circumference between two points.

An opening through a headland with a roof of rock above it.

One of the three domains; it contains prokaryotic microorganisms that are genetically distinct from bacteria.

The location and associations of an archaeological find, including nearby objects and its relationship to buildings or deposits.

Material evidence from the past, such as coins, buildings, tombstones and writing tablets, used to investigate historical societies.