encroachment
Encroachment (noun) means the act of gradually intruding on someone else's land, rights or area of authority, or the intrusion itself. Example: “Residents objected to the encroachment of housing on the green belt.”
How to use encroachment
Learner’s notesIn plain EnglishSlowly taking over land or rights that belong to someone else.
Formal; common in law, property, planning and politics.
The usual preposition is "on", though "upon" is common in legal writing.
Trace the full origin ↓Fill the gap
Can you complete this real example?
Residents objected to the _____ of housing on the green belt.
Etymology
From encroach, from Old French encrochier "to seize, hook on to", from en- and croc "hook", with the noun suffix -ment.