Definition

1. Verb phrase:
   • To cross the line/demarcation line: The primary historical meaning refers to the act of illegally crossing a military or political demarcation line, most famously the Ben Hai River during the division of Vietnam.
   • To cross over (to the other side): More broadly, it can mean to defect or to escape from one zone, area, or side to another, often implying a significant and risky journey.

Usage Examples

• Verb phrase:
  • Nhiều người đã tìm cách vượt tuyến để đoàn tụ với gia đình. (Many people tried to cross the demarcation line to reunite with their families.)
  • Câu chuyện kể về một người lính quyết định vượt tuyến. (The story is about a soldier who decided to cross over to the other side.)

Advanced Usage

• The term is deeply tied to the historical context of Vietnam's division from 1954 to 1975. It specifically connotes the dangerous, clandestine journey from North to South or vice-versa across the 17th parallel.
• In modern, extended metaphorical use, it can sometimes describe overcoming a major barrier or limit, though this is less common.

Variants and Related Words

• Vượt biên (verb phrase): to cross the border (often referring to leaving the country by land or sea).
  • Họ đã vượt biên trong một đêm mưa gió. (They crossed the border on a stormy night.)

Synonyms

• To cross the demarcation line
• To defect (in a military/political context)
• To escape across the line

Related Idioms

• While "vượt tuyến" itself is often used as a set phrase, it is central to many historical narratives and personal stories of the Vietnam War period, encapsulating the themes of risk, separation, and the desire for reunion or freedom.