The forcible inclusion or entry of an external group or individual; the act of intruding.
The insertion of a phoneme into the pronunciation of a word despite its absence from the spelling. (e.g. intrusive r)
A structure that lies within a historic district but is nonhistoric and irrelevant to the district.
Magma forced into other rock formations; the rock formed when such magma solidifies.
The entry without consent of an individual or group into an area where they are not wanted.
A military action consisting of armed forces of one geopolitical entity entering territory controlled by another such entity, generally with the objective of conquering territory or altering the established government.
The breaching of the skin barrier.
The spread of cancer cells, bacteries and such to the organism.