Noun

(en noun)

An aggressive movement into somewhere; an invasion.

Noun

(en noun)

The forcible inclusion or entry of an external group or individual; the act of intruding.

* He viewed sales calls as an unwelcome intrusion .

*{{quote-magazine, date=2012-12-14

, author=Simon Jenkins, authorlink=Simon Jenkins , title=We mustn't overreact to North Korea boys' toys , volume=188, issue=2, page=23 , date=2012-12-21 , magazine= citation , passage=The threat of terrorism to the British lies in the overreaction to it of British governments. Each one in turn clicks up the ratchet of surveillance, intrusion and security. Each one diminishes liberty.}}

(geology) Magma forced into other rock formations; the rock formed when such magma solidifies.