encroachment

Etymology

encroach + -ment

noun

1. An entry into a place or area that was previously uncommon; an advance beyond former borders; intrusion; incursion.
   At the same time, the encroachment of vegetation proceeds apace, and broom and brambles have already made portions of the line impassable, even on foot. 1949 November and December, “Notes and News: Festiniog and Welsh Highland Railways”, in Railway Magazine, page 408
2. An intrusion upon another's possessions or rights; infringement.
3. That which is gained by such unlawful intrusion.
4. (law) An unlawful diminution of the possessions of another.