General term for single use consumable items like Fire Protection Potions produced by Alchemy, stamina buffing food like Tender Wolf Steak or rogue energy boosters like Thistle Tea. Using consumables can greatly increase your power, but can also be very hard on the wallet.
Consumables also includes certain conjured items that can be used as food or drink. For example, food and water conjured by Mages. These consumables are free, as long as you find a cooperative mage.