encroachment

noun4

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
2. •
   An intrusion upon another's possessions or rights; infringement.
3. •
   An unlawful diminution of the possessions of another.
4. •
   That which is gained by such unlawful intrusion.