/bawr"deuhr luyn'/ , adj.
1. on or near a border or boundary.
2. uncertain; indeterminate; debatable: not an alcoholic, but a borderline case.
3. not quite meeting accepted, expected, or average standards.
4. approaching bad taste or obscenity: He made several borderline remarks that offended them.
n.
5. a person suffering from borderline personality.
[ 1865-70; BORDER + LINE 1 ]
Syn. 3. marginal, problematic, uncertain, doubtful.