encroachment

noun

1. (uncountable, usually)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.”

   “[…] the largest extents of encroachments were found in the Dry Zone Districts, such as Anuradhapura, Kurunegala and Moneragala, where encroachable State lands were readily available (Table I). […] Between 1979-1985, some 104,490 new encroachments covering an extent of 70,646 Ha (174,566 acres) took place with high encroachments in the Central Province (40% increase over 1978). The Western Province comes second. This excludes […]”

2. (uncountable, usually)An intrusion upon another's possessions or rights; infringement.

   “The Legislative department derives a superiority in our Governments from other circumstances. Its constitutional powers being at once more extensive, and less susceptible of precise limits, it can, with the greater facility, mask, under complicated and indirect measures, the encroachments which it makes on the coördinate departments.”

   “Ah! my brother, we do well to watch our birthright jealously; the least invasion on the meanest peasant, the slightest encroachment of the powerful, are not matters to be neglected—such are the first steps of tyranny.”

3. (uncountable, usually)That which is gained by such unlawful intrusion.
4. (uncountable, usually)An unlawful diminution of the possessions of another.