doubleline
nounUK /ˈdʌbəl laɪn/
US /ˈdʌbəl laɪn/
A double line is two lines drawn close together side by side.
The teacher asked us to write our names on the double line at the top of the page.
OTHER MEANINGS
2. A pair of railway tracks running side by side.
The train switched to the double line to let the express pass.
3. A fishing line made of two strands twisted together for extra strength.
He tied a double line to the hook before casting into the river.
4. A mark consisting of two parallel strokes used in printing or writing.
The editor put a double line under the heading to show it should be bold.