A dotted line is a line drawn as a row of separate points. Cut along the dotted line, sign on the dotted line, a dotted line on the map.
Sign on the dotted line is the standard phrase for committing to an agreement, since forms once printed one for the signature. On a map it usually marks something uncertain or not yet built.
1noundotted lineA line drawn as a row of separate points.
“Fold the paper along the dotted line to make a card.”
dotted line is a line.
Practised in Light & Shadow, Shapes & Lines