Excess Stock is a term used in inventory management, and is often called a number of different things; overstock, stock surplus, excessive stock, or excess inventory.
Source - easystock.com
Obsolete inventory is a term that refers to inventory that is at the end of its product life cycle. This inventory has not been sold or used for a long period of time and is not expected to be sold in the future. This type of inventory has to be written down and can cause large losses for a company.
Source - investopedia.com