Definition of intrusions:
(n) :
The forcible inclusion or entry of an external group or individual; the act of intruding.
(n) :
(psychology) An involuntarily arising idea or memory that is nuisant and falsifies an accurate impression of the world.
(n) :
(phonology) The insertion of a phoneme into the pronunciation of a word despite its absence from the spelling. (e.g. intrusive r)
(n) :
A structure that lies within a historic district but is nonhistoric and irrelevant to the district.
(n) :
(geology) Magma forced into other rock formations; the rock formed when such magma solidifies.