Any line that joins the north and south poles has the same longitude
at every point on it. It's called the 'meridian' of that longitude.
The imaginary line that runs north and south from the North Pole to the South Pole at 0 degrees longitude is called the Prime Meridian.
The lines that run north and south are called meridians of longitude. (The north and south poles are the ends of every meridian, so each one only goes half-way around the globe.)
The imaginary line that connects the North Pole to the South Pole at the surface of the planet is called the Earth's axis. It is an imaginary line around which the Earth rotates.
Every meridian is an imaginary semi-circle between the north and south poles. There are an infinite number of them, each one is more than 12,000 miles long, and every point on the same meridian has the same longitude.
line of longitude. Or a longitudinal line.
"Meridian of longitude"
Latitude.
The imaginary line that runs north and south from the North Pole to the South Pole at 0 degrees longitude is called the Prime Meridian.
The lines that run north and south are called meridians of longitude. (The north and south poles are the ends of every meridian, so each one only goes half-way around the globe.)
The imaginary line that connects the North Pole to the South Pole at the surface of the planet is called the Earth's axis. It is an imaginary line around which the Earth rotates.
An imaginary line which runs round the globe, called the "equator".
Every meridian is an imaginary semi-circle between the north and south poles. There are an infinite number of them, each one is more than 12,000 miles long, and every point on the same meridian has the same longitude.
Assuming the question is about the prime meridian, it is the imaginary line joining the North and South poles which passes through a specific point in the Greenwich observatory in London.
line of longitude. Or a longitudinal line.
Earth's Axis
An imaginary line which runs round the globe, called the "equator".
longitudinal lines run north/south; Latitudinal lines run east/west