What term describes unwanted radio energy transmitted just outside the necessary bandwidth?

Out-of-band emissions are defined as unwanted radio frequency energy that falls immediately outside the necessary bandwidth for the type of transmission being used. These emissions are often the result of the modulation process, such as splatter from an overmodulated voice signal or key clicks from a CW transmitter. This is distinct from spurious emissions or harmonic emissions, which occur at frequencies much further away from the operating frequency. "Spurious emissions" is a broader term that includes harmonics and parasitic emissions, but "out-of-band" specifically refers to energy spilling just outside the designated channel bandwidth.