A Line

1. a long, narrow mark or band
2. a length of cord, rope, wire, or other material serving a particular purpose:
3. a horizontal row of written or printed words
4. a row of people or things
5. an area or branch of activity
6. a connected series of military fieldworks or defences facing an enemy force

 - (on a map or graph) a curve connecting all points having a specified common property
 - A contour or outline considered as a feature of design or composition:
 - Crisp architectural lines
 - Each of the very narrow horizontal sections forming a television picture
 - Physicsa narrow range of the spectrum that is noticeably brighter or darker than the adjacent parts
 - The equator
 - A notional limit or boundary
 - A series of related things:
 - The bill is the latest in a long line of measures to protect society from criminals
 - A telephone connection or service