Quantum decoherence refers to the loss of coherence, or the breakdown of quantum mechanics, in a system due to its interaction with the environment. Some synonyms for quantum decoherence include quantum dissipation, quantum decoherence loss, and quantum noise. These terms describe the same process of a quantum system interacting with its environment, leading to the loss of its quantum properties. Other related terms include quantum entanglement, quantum superposition, and quantum coherence, which describe the opposite of decoherence - when a quantum system is in a pure quantum state, has well-defined properties, and shows quantum behavior. Understanding these concepts is crucial in the development of quantum technologies such as quantum computing, cryptography, and sensing.