“18-point” can mean:

• Typography: a font size of 18 points (quite large text, often used for headings or titles).
• Scoring / rating: a system or result involving 18 points (e.g., an 18-point lead in a game or contest).
• Hunting (rare): a “18-point buck” refers to a deer with 18 antler points.

In general, it means something measured, scored, or sized at eighteen points, depending on context.