Tending to annihilate or capable of causing complete destruction; having the nature of annihilation.
From annihilate plus -ive (suffix forming adjectives meaning 'tending to'). From Latin 'annihilare' with standard English productive suffix.
Physicists use 'annihilative forces' to describe the collision of matter and antimatter—a word created by medieval theologians now explains real particle physics!
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