A limitation put on you by others, society, circumstance, environment, or something else outside yourself.
A perceived personal limitation, or perhaps some you’re limiting yourself.
A beginning or ending.
An extreme, or something “far out” (such as “the edge of the world,” “the edge of reason,” or “the limit of your patience”).
“The best,” “the most,” or another superlative concept.
For more clues, consider the context of and your feelings about the limit or boundary.
See also: Edge, Coming to an; Ledge or Cliff; Divider; Restrained; Top; Bottom; Infinite; Frame