Refers to organic material that is no longer alive, often used in ecological or agricultural contexts.

Can refer to anything that has lost its function or relevance, often used metaphorically.

जो अपनी कार्यक्षमता या प्रासंगिकता खो चुका है

English Usage: After the project failed, it felt like all the ideas we had were just dead matter.

Hindi Usage: जब प्रोजेक्ट विफल हो गया, तो ऐसा लगा कि हमारे पास मौजूद सभी विचार बस मृत पदार्थ हैं.