Definition

1. Proper noun:
   • An imaginary line on the Earth's surface: The International Date Line is an imaginary line that roughly follows the 180° meridian of longitude in the Pacific Ocean. It is the line where the calendar date changes.

Usage

• The International Date Line is used to designate the place where each new calendar day begins.
• Crossing the International Date Line causes the date to change by one day.

Examples

• Proper noun:
  • When you cross the International Date Line traveling east, you subtract a day.
  • The island nation of Fiji lies just west of the International Date Line.
  • The concept of the International Date Line is essential for global timekeeping and travel.

Advanced Usage

• "across the International Date Line": Referring to locations or travel on opposite sides of this line.
  • Communicating with someone across the International Date Line requires careful attention to the day and time.
• "International Date Line shift": A historical or proposed adjustment to the line's path, often for political or economic reasons.
  • Kiribati's eastern islands enacted an International Date Line shift in 1995 so the entire nation could share the same weekday.

Variants and Related Words

• Date Line (noun): A common shortened form for "International Date Line."
  • The ship will cross the Date Line at midnight.
• 180th meridian (noun): The line of longitude at 180°, which the International Date Line approximately follows.
  • The 180th meridian is directly opposite the Prime Meridian.

Synonyms

• Calendar line: A less common term describing the same concept.

Related Phrases

• Cross the date line: The act of traveling over the International Date Line.
  • After we cross the date line, it will suddenly be tomorrow.

Noun

1. an imaginary line on the surface of the earth following (approximately) the 180th meridian