encloser

noun

1. (historical)Someone who appropriates common land.

   “It was said, for example, that […] the families of notorious enclosers always died out in three generations […].”

   “Ironically, it was the encloser who had acted in an unbounded manner by violating the institutional boundaries of local community power.”

   “In one episode during the long-running dispute over enclosure at Grewelthorpe Moor in Yorkshire, the women of the community followed the encloser on to the moor and, ‘fallinge downe upon their knees, and some of them weepinge for the loss of their Comon, desired…[him] to be good unto them’.”

2. More generally, someone or something that encloses something.
3. An object, procedure, or other portion of code that defines the scope of a variable.