• noun:   the emergence of a tooth as it breaks through the gum
• noun:   (of volcanos) pouring out fumes or lava (or a deposit so formed)
• noun:   symptom consisting of a breaking out and becoming visible
• noun:   a sudden violent spontaneous occurrence (usually of some undesirable condition)
• noun:   the sudden occurrence of a violent discharge of steam and volcanic material
• noun:   a sudden very loud noise

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