Encroachment

In football, it's a five-yard penalty called when a defensive player gets too close to the offensive line before a play is snapped.

In the business world, the word has a similar meaning. If a person violates your property rights (crosses into your territory a la a defensive back getting near the offensive lineman), they're committing encroachment.

For example, your neighbor decides to widen her driveway. Once all the work is done, you notice that a small part of the new asphalt now sits across the property line. The driveway is encroaching on your property.

Hopefully, you and your neighbor can get together and figure out a fair resolution. Maybe you could sell her the thin slice of property that she's taken over. Maybe she could pay you a small annual fee to "rent" that bit of property (maybe in the form of fresh baked brownies delivered promptly every Sunday...maybe in cash, we don't know, see what you can get).

If you don't work it out, the next steps are mediation or a lawsuit. At this point, brownies are off the table.