Prime Meridian.
Lines of longitude measure how far something is east or west of the Prime Meridian.
west and east
East-West
Longitude lines.
They measure east and west
Lines of longitude run north-south and measure east-west.
Longitude is the correct answer
east west
east west
Either or both.
Lines of longitude run north-south and measure east-west.
Longitude lines. They are also called meridians.