Invasion (noun)

1. An instance of invading a country or territory, especially with military force.
2. A large number of people or things entering a place, typically in an intrusive or overwhelming way.

Origin:

Late 16th century: from latin invasio(n-), from invadere 'go into' (see invade).

Examples:

1. The invasion of the enemy territory was swift and decisive.
2. The invasion of the capital city by the rebels was unexpected.
3. The invasion of tourists during the summer months overwhelmed the small town.
4. The invasion of privacy by the media was a major concern.
5. The invasion of the invasive species had a negative impact on the local ecosystem.