ACT - Something done, a deed.
ARC - A directed edge.
ART - Human effort to imitate, supplement, alter, or counteract the work of nature.
CAR - A wheeled vehicle, drawn by a horse or other animal.
CAT - Any similar animal of the family Felidae, which includes lions, tigers, bobcats, etc.
RAT - A medium-sized rodent belonging to the genus Rattus.
TAR - A black, oily, sticky, viscous substance, consisting mainly of hydrocarbons derived from organic materials such as wood, peat, or coal.
CART - A small, open, wheeled vehicle, drawn or pushed by a person or animal, more often used for transporting goods than passengers.
CIRCA - Approximately, about.
ARCTIC - Being extremely cold, snowy, or having other properties of extreme winter associated with the Arctic.