Boundary
Boundary ({not transcribed}) , noun
[From Bound a limit; compare Late Latin bonnarium piece of land with fixed limits.]
That which indicates or fixes a limit or extent, or marks a bound, as of a territory; a bounding or separating line; a real or imaginary limit.
But still his native country lies
Beyond the boundaries of the skies.
That bright and tranquil stream, the boundary of Louth and Meath.
Sensation and reflection are the boundaries of our thoughts.