Definition from Wiktionary, the free dictionary
- nearly; not clearly on one side or the other of a border or boundary, ambiguous.
- He is borderline hypoglycemic and needs to monitor his sugar intake.
- I would rather hire a talented layman than a university graduate with borderline qualifications.
- Showing bad taste.
- Your borderline remarks about my aunt's dress destroyed my evening.
not clearly on one side or other of a boundary
borderline (plural borderlines)