Explosion (?), n. [L. explosio a driving off by clapping: cf. F. explosion explosion. See Explode.] 1. The act of exploding; detonation; a chemical action which causes the sudden formation of a great volume of expanded gas; as, the explosion of gunpowder, of fire damp, etc.
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2. A bursting with violence and loud noise, because of internal pressure; as, the explosion of a gun, a bomb, a steam boiler, etc.
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3. A violent outburst of feeling, manifested by excited language, action, etc.; as, an explosion of wrath.
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A formidable explosion of high-church fanaticism. Macaulay.
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4. a sudden and substantial increase; a rapid acceleration; as, the population explosion.
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