bourn, verge, curbstone†, but, pale, reservation; termination, terminus;
stint, frontier, precinct, marches; backwoods.
boundary line, landmark; line of demarcation, line of
circumvallation†; pillars of Hercules; Rubicon, turning point; ne plus
ultra [Lat.]; sluice, floodgate.
Adj. definite; conterminate†, conterminable†; terminal, frontier;
bordering.
Adv. thus far, thus far and no further.
Phr. stick to the reservation; go beyond the pale.