"a row of closely spaced dots will look like a continuous line"

• a straight or curved continuous extent of length without breadth
• a direct course

  "the ball rose in a straight line"

• a furrow or wrinkle in the skin, especially on the face

  "there were new lines round her eyes and mouth"

• a contour or outline considered as a feature of design or composition

  "crisp architectural lines"

• (on a map or graph) a curve connecting all points having a specified common property
• a line marking the starting or finishing point in a race

  "a good position at the start line will put you in the front rank on the first leg"

• (in football, hockey, etc.) the goal line

  "Dunne was on hand to bundle the ball over the line"

• the equator
• a notional limit or boundary

  "the issue of peace cut across class lines"

• each of the very narrow horizontal sections forming a television picture
• a narrow range of the spectrum that is noticeably brighter or darker than the adjacent parts
• the level of the base of most letters, such as h and x, in printing and writing
• denoting an image consisting of lines and solid areas, with no gradation of tone

  "a line block"

• each of (usually five) horizontal lines forming a stave in musical notation
• a sequence of notes or tones forming an instrumental or vocal melody

  "a powerful melodic line"

• a dose of a powdered narcotic drug, especially cocaine, laid out in a line ready to be taken

"Lily pegged the washing on the line"

• a length of sterile tubing inserted into a vein or artery in order to provide temporary access, typically so as to administer fluids or withdraw blood

  "he's having an op this morning to put a line in his chest for IV drugs"

• a telephone connection or service

  "I've got Inspector Jackson on the line for you"

• a railway track

  "passengers were hit by delays caused by leaves on the line"

• a branch or route of a railway system

  "the Glasgow to London line"

• a company that provides ships, aircraft, or buses on particular routes on a regular basis

  "a major shipping line"

"take the cursor up one line and press the delete key"

• a part of a poem or song forming one row of written or printed words

  "each stanza has eight lines"

• the words of an actor's part in a play or film

  "he couldn't seem to remember his lines and had to read his dialogue off boards"

• an amount of text or number of repetitions of a sentence written out as a school punishment

  "five hundred lines to anyone caught sneaking in before the bell!"

"a line of altar boys proceeded down the aisle"

• a queue
• a connected series of people following one another in time (used especially of several generations of a family)

  "we follow the history of a family through the male line"

• a series of related things

  "the bill is the latest in a long line of measures to protect society from criminals"

• a range of commercial goods

  "the company intends to hire more people and expand its product line"

"the stresses unique to their line of work"

• a direction, course, or channel

  "he opened another line of attack"

• a manner of doing or thinking about something

  "you can't run a business on these lines"

• an agreed approach; a policy

  "the official line is that there were no chemical attacks on allied troops"

• a false or exaggerated remark or story

  "he fed me a line about some nightclubbing Japanese photographer"

"raids behind enemy lines"

• an arrangement of soldiers or ships in a column or line formation; a line of battle
• regular army regiments (as opposed to auxiliary forces or household troops)

"a processional route lined by people waving flags"

"deep wrinkles lined his face"