The term "auction unit" can be defined as an item or group of items that are put up for auction. There are several synonyms for this phrase, including lot, consignment, sale, and bid. Each of these words refers to a different aspect of an auction unit. A lot can refer to a single item or a group of items that are sold together. A consignment is a group of items that are sold on behalf of someone else. A sale is a general term for an event where items are sold, and a bid refers to a specific offer to buy an item at auction. Regardless of the term used, all refer to the auction unit and the process of buying and selling items at auction.