What is a partial separation of parts, with or without a perceptible opening; a chink or fissure; a narrow breach; a crevice; as, a crack in timber, or in a wall, or in glass called?

crack — A partial separation of parts, with or without a perceptible opening; a chink or fissure; a narrow breach; a crevice; as, a crack in timber, or in a wall, or in glass. (Webster's 1913.)

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