Have you Googled Borderline Personality Disorder? That would give you some idea of the symptoms of the full illness. What they are saying, it seems, is that you have some of the symptoms, but not enough for diagnosis of BPD itself.
There are 9 criteria, and to have diagnosis of BPD someone needs to fulfil 5 of those 9.
The 9 criteria are -
Frantic efforts to avoid real or imagined abandonment
A pattern of unstable and intense interpersonal relationships characterized by alternating between extremes of idealization and devaluation
Identity disturbance: markedly and persistently unstable self-image or sense of self
Impulsivity in at least two areas that are potentially self-damaging (e.g., spending, sex, substance abuse, reckless driving, binge eating)
Recurrent suicidal behavior, gestures, or threats, or self-mutilating behavior
Affective instability due to a marked reactivity of mood (e.g., intense episodic dysphoria, irritability, or anxiety usually lasting a few hours and only rarely more than a few days)
Chronic feelings of emptiness
Inappropriate, intense anger or difficulty controlling anger (e.g., frequent displays of temper, constant anger, recurrent physical fights)
Transient, stress-related paranoid ideation or severe dissociative symptoms
So, having 'traits' means that you have maybe several of those symptoms.
For example, I also have Borderline traits, I have the
~ frantic attempts to avoid real/imagined abandonment
~ paranoia and dissociation
The other symptoms come and go, but are not present all the time.
Does that help some?