To destroy completely or reduce to nonexistence. The powerful storm threatened to annihilate the small coastal town.
To defeat utterly or decisively. The home team managed to annihilate their opponents with a score of 10-0.
Physics: (of a particle and its antiparticle) to collide and convert their mass into energy, typically in the form of photons. When a positron meets an electron, the two particles annihilate and release gamma radiation.