What term refers to a solid, liquid, or contained gaseous material that is no longer useful?

The term that is most correctly associated with a solid, liquid, or contained gaseous material that is no longer useful is "Waste." Waste encompasses materials that are discarded because they are no longer needed or wanted. This can include various forms of material across different states, such as solid waste (like trash), liquid waste (like wastewater), or gases that are no longer usable or safe.

While hazardous waste refers specifically to waste that poses potential risks to health or the environment due to its chemical characteristics, it is a subset of waste rather than a general term. Byproducts are materials produced in the process of producing another product, which may still have value or utility. Disposal material can be vague and does not carry the same specific connotation related to the broader concept of waste. Thus, waste is the most appropriate term to describe materials that have reached the end of their usefulness.