A tidal disruption event (TDE) is a star being pulled apart by the tidal forces of a black hole. While part of the star is subsumed, it is, for a time, "spread out in pieces" and some of the star is ejected. This type of event was theorized in 1975 but observations have been ascribed to this type of event only in the last decade, with discussion about how to distinguish such an event from "ordinary active galactic nucleus activity". Observations include X-rays, gamma rays, and ultraviolet, the latter presumably from clouds heated by the event, e.g., jets produced. Events that show particularly high surges in the X-ray band have been termed X-ray TDEs (X-ray tidal disruption events).
The term tidal disruption flare (TDF) is used for the same type of event but can be used specifically to refer to the emitted electromagnetic radiation of a TDE.