borderline

Etymology

border + line

adj

1. Nearly; not clearly on one side or the other of a border or boundary, ambiguous.
   I would rather hire a talented layman than a university graduate with borderline qualifications.
2. Showing bad taste.
   Your borderline remarks about my aunt's dress destroyed my evening.
3. Exhibiting borderline personality disorder.
   She clearly has borderline and narcissistic features and she meets the criteria for a rapid cycling bipolar disorder, as well as for a generalized anxiety disorder. She has a severe binge eating disorder and has gained 65 pounds since[…] 2003-12-08, Leslie Atkinson, Research Scientist at the Psychiatry Research Unit Susan Goldberg, Susan Goldberg, Attachment Issues in Psychopathology and Intervention, Routledge, page 192

adv

1. Nearly; not entirely but nevertheless to a great extent.
   He is borderline hypoglycemic and needs to monitor his sugar intake.
   I expected him to be super boring but he was actually borderline funny!

noun

1. (countable) A boundary or accepted division; a border.
   She lives on the borderline between reality and madness.
2. (uncountable) Short for borderline personality disorder.
   The four overlapping concepts of borderline were as follows : (1) A residual model […] (2) An affective disorder model, which considered BPD as an affective spectrum illness displaying prominent[…] 2001-07-23, Howard S. Friedman, The Disorders: Specialty Articles from the Encyclopedia of Mental Health, Gulf Professional Publishing, page 109
   … you should consider it! People with Borderline are especially affected by the unconditional affection parenting a pet can provide. 2014-12-16, Amber Zufelt, Chasing Butterflies: The Ultimate Guide to Surviving Borderline Personality Disorder, Lulu.com, page 40
   Subsequent conceptualizations of borderline were based on important contributions from psychoanalysts, […] As a result of its inclusion, appearing as “borderline personality disorder,” the construct gained legitimacy[…] 2011-11-08, Paula K. Lundberg-Love, Kevin L. Nadal, Michele A. Paludi, Women and Mental Disorders [4 volumes], ABC-CLIO, page 155
3. (countable) An individual who has borderline personality disorder.
   As an example of their affective profile, borderlines are set apart from passive aggressives by having more marked social anxiety […] and greater sensitivity […] 1995, Eugene E. Levitt, Edward Earl Gotts, The Clinical Application of MMPI Special Scales, page 80

verb

1. (transitive) To border, or border on; to be physically close or conceptually akin to.