borderline

(bôrˈdər-līnˌ)

1. A line that establishes or marks a border.
2. An indefinite area intermediate between two qualities or conditions: The borderline between love and hate is often thin.

1. a. Verging on a given quality or condition: borderline poverty.
   b. Of a questionable nature or quality: an applicant with borderline qualifications.
2. a. Psychology Relating to any phenomenon that is intermediate between two groups and not clearly categorized in either group: a borderline state showing the characteristics of both neurotic and psychotic reactions.
   b. Relating to a condition characterized by a pattern of instability in mood, interpersonal relations, and self-image, and manifested by self-destructive, impulsive, and inconsistent behavior: the borderline syndrome.