eruption

noun

1. 1

   the emergence of a tooth as it breaks through the gum

2. 2

   a sudden very loud noise

3. 3

   a sudden violent spontaneous occurrence (usually of some undesirable condition)

   the outbreak of hostilities

4. 4

   the sudden occurrence of a violent discharge of steam and volcanic material

5. 5

   (of volcanos) pouring out fumes or lava (or a deposit so formed)

6. 6

   symptom consisting of a breaking out and becoming visible