Your borderline remarks about my aunt's dress destroyed my evening.
{s} on the edge, approaching the limit; questionable; on the border between to areas
The borderline between two different or opposite things is the division between them. a task which involves exploring the borderline between painting and photography
of questionable or minimal quality; "borderline grades"; "marginal writing ability
Something that is borderline is only just acceptable as a member of a class or group. Some were obviously unsuitable and could be ruled out at once. Others were borderline cases
of questionable or minimal quality; "borderline grades"; "marginal writing ability"