annihilated

Annihilated is the past participle of annihilate, a verb meaning to destroy utterly, wipe out, or reduce something to nothing. In everyday language, objects, ideas, or entities can be described as annihilated when they are completely eliminated or rendered unusable. The term can be used literally, as when a structure is destroyed, or figuratively, as when a debate is said to be annihilated by a decisive argument.

In physics, annihilation denotes a specific interaction between a particle and its antiparticle, in which their combined mass is converted into energy, typically in the form of photons. Electron–positron annihilation is the best-known example, yielding gamma-ray photons with energies of 511 keV each, though other final states are possible at higher energies. Annihilation is governed by conservation laws and is distinct from radioactive decay or simple scattering processes.

In mathematics, the term has a more abstract usage. The annihilator of a subspace W of a vector space V, often denoted W^0, is the set of all linear functionals on V that vanish on W. This concept extends to bilinear forms, modules, and differential operators, where an operator or functional is said to annihilate a space if its application yields zero. The figurative sense—removing an influence or effect by a complementary action—also appears in mathematical explanations.

Etymology: annihilate comes from the Latin nihil meaning nothing, via French anéantir or related English adaptations; the sense of reducing to nothing is reflected in its early modern usage. The noun annihilation and related terms are common in science and mathematics.