Adbertos: Sacrifice, specifically one’s life for the greater cause. Not necessarily in death, it can mean a lifelong servitude either chosen or forced by inheritance.
Alchemist: The most senior of the Druid priests, he has a heightened gift of prophecy. He is charged with overseeing the burials on Mona and destined never to leave the isle.
Alum: A naturally occurring rock that can be used as a blood coagulant. It also has antibacterial properties and acts as an antiperspirant and deodorant.
Bard: Reciter of poetry, singer of songs and story teller.
Battlements: A wall around the top of a castle, with spaces (crenels) through which projectiles could be thrown.
Caligae: A heavy-soled Roman military sandal with iron hobnails. An effective weapon against a fallen enemy.
Carpentom: A small, lightweight chariot.
Castrum: A fortified fortress.
Chaplet: A decorative circle of flowers worn on the head.
Char cloth (charpaper): A swatch of fabric made from vegetable fiber (such as linen) used as a slow-burning fuel of very low ignition temperature.
Crenels: A gap in the top of a castle wall or parapet, used for firing/throwing missiles.
Druid: A priest or ovate of an ancient religion practiced in Britain. A worshiper of the forces of nature.
Fly agaric mushroom: A large white-gilled, white-spotted, usually red mushroom, noted for its hallucinogenic properties.
Focale: A scarf worn by a Roman soldier to protect the neck from chafing caused by constant contact with his armor.
Galea: Soldier's helmet.
Gladius: A Roman short sword.
Ley: Lines of spiritual energies believed to run beneath the ground. Where these Ley Lines converge, typically beneath a hill, the energy is greatly increased. The Druids were thought to be able to locate these lines through their connection to the earth.
Mantle: A Druid’s cloak. A large rectangle of finely woven woolen fabric without a hood or fastenings. Fixed at the neck with a penannular broach capable of piercing the fabric.
Mordant: A substance that fixes a dye in and on textiles or leather.
Oppidum (plural oppida): A large defended British settlement.
Ovate: An apprentice of the Druid faith.
Palm: Unit of measurement equivalent to 3”.
Paludamentum: A cloak or cape fastened at one shoulder, mostly worn by Roman military commanders.
Parapet: A low protective wall. A bank of soil, rubble or stone piled up along the edge of   a military trench for protection from enemy fire.
Penannular Broach: A circular, concave metal disc with a hole at the center where the cloth of a cloak would be pulled through. A long matching pin would then be inserted through the cloth to hold it fast.
Pilum: A heavy javelin whose range was about 30 meters.
Praetorian Guard: Bodyguards used by Roman Emperors.
Priest: Highest ranking order of the Druid religion.
Procurator: The title of various officials of the Roman Empire.
Salararius: A paid mercenary or assassin.
Torc: A decorative solid neck ornament believed to protect the wearer. An almost complete circle of metal that would be forced open to put in place and then resized to fit.
Trimarcisia: A closely bonded fighting unit of three, the warrior, his armorer and the charioteer.
Trousers (Braccae): Long pants made primarily of leather or wool. Popular among Roman legionaries in cooler climates.
Tunic: A wide-necked garment with or without sleeves that extends to the hip or knee. Worn by both men and women it is usually loose fitting, worn with a belt or gathered at the waist.
Twat: A highly offensive term for a woman's vagina or genital area or for somebody regarded as unintelligent or worthless.

Kingdoms, Cities and Towns of Britannica

Catuvellauni: Londinium (London), Verlamion (St. Albans)
Atrebates: Calleva Atrebatum (Silchester)
Trinovantes: Camulodunum (Colchester)
Canti: Rutupiae (Rochester), Durobrivae (Medway)
Regnenses: Noviomagus Reginorum (Chichester)
Belgae: Portus Adurni (Portsmouth), Sarum (Salisbury)
Dumnonii: Isca Dumnoniorum (Exeter), Nanstallon (near Okehampton), Lulyn (near Penzance)
Silures: Caerdydd (near Cardiff)
Dobunni: Aqua Sulis (Bath), Cheltenham
Cornovii: Wulfruneheantun (Wolverhampton), Caer Caradoc (Church Stretton), Deva Victrix (Chester), Lodelowe (Ludlow)
Coritani: Lindum Colonia (Lincoln), Ratae Corieltauvorum (Leicester)
Iceni: Venta Icenorum (Norwich), Thetford
Brigantes: Loidisium (Leeds)
Isles: Vectis (Isle of Wite) (Belgae/Regnenses), Mona (Anglesey) (Ordovices)