1. increase rapidly and in an uncontrolled manner

e.g. The population of India is exploding
The island's rodent population irrupted

Synonym: explode

2. erupt or intensify suddenly

e.g. Unrest erupted in the country
Tempers flared at the meeting
The crowd irrupted into a burst of patriotism

Synonym: eruptflare upflarebreak openburst out

3. enter uninvited

e.g. They intruded on our dinner party
She irrupted into our sitting room

Synonym: intrude