| indistinct(uncertain, shaky, vague, unclear, ambiguous) |
| periphery(noun, edge, border, frontier, trimming) |
| precarious(adjective, uncertain, unstable, doubtful, shaky) |
| terminal(noun, top, limit, extreme, edge) |
| ambivalent(adjective, inexact) |
| brim(noun, edge, trim, border, trimming) |
| chancy(adjective, clear, delicate, certain, uncertain) |
| confine(noun, verb, top, limit, extreme) |
| debatable(adjective, open, uncertain, doubtful, dubious) |
| dividing line(expression, idiom, distinction, margin) |
| iffy(adjective, clear, open, delicate, informal) |
| last in line |
| minimal |
| problematical(adjective, clear, certain, ambiguous, debatable) |
| skirt |
| ambit(noun, border, frontier) |
| betwixt and between(expression, adjective, idiom, open, uncertain) |
| border line(noun, expression, idiom) |
| borderland |
| bounds(noun, border, frontier) |