n.

1. a formation of people or things one beside another
   
   • the line of soldiers advanced with their bayonets fixed
   • they were arrayed in line of battle
   • the cast stood in line for the curtain call
2. a mark that is long relative to its width
   
   • He drew a line on the chart
3. a formation of people or things one behind another
   
   • the line stretched clear around the corner
   • you must wait in a long line at the checkout counter
4. a length (straight or curved) without breadth or thickness; the trace of a moving point
5. text consisting of a row of words written across a page or computer screen
   
   • the letter consisted of three short lines
   • there are six lines in every stanza
6. a single frequency (or very narrow band) of radiation in a spectrum
7. a fortified position (especially one marking the most forward position of troops)
   
   • they attacked the enemy's line
8. the methodical process of logical reasoning;
   argumentation, logical argument, line of reasoning
   
   • I can't follow your line of reasoning
9. a conductor for transmitting electrical or optical signals or electric power;
   cable, transmission line
10. a connected series of events or actions or developments;
    course
    
    • the government took a firm course
    • historians can only point out those lines for which evidence is available
11. a spatial location defined by a real or imaginary unidimensional extent
12. a slight depression in the smoothness of a surface;
    wrinkle, furrow, crease, crinkle, seam
    
    • his face has many lines
    • ironing gets rid of most wrinkles
13. a pipe used to transport liquids or gases;
    pipeline
    
    • a pipeline runs from the wells to the seaport
14. the road consisting of railroad track and roadbed;
    railway line, rail line
15. a telephone connection;
    telephone line, phone line, telephone circuit, subscriber line
16. acting in conformity
    
    • in line with
    • he got out of line
    • toe the line
17. the descendants of one individual;
    lineage, line of descent, descent, bloodline, blood line, blood, pedigree, ancestry, origin, parentage, stemma, stock
    
    • his entire lineage has been warriors
18. something (as a cord or rope) that is long and thin and flexible
    
    • a washing line
19. the principal activity in your life that you do to earn money;
    occupation, business, job, line of work
    
    • he's not in my line of business
20. in games or sports; a mark indicating positions or bounds of the playing area
21. (often plural) a means of communication or access;
    channel, communication channel
    
    • it must go through official channels
    • lines of communication were set up between the two firms
22. a particular kind of product or merchandise;
    product line, line of products, line of merchandise, business line, line of business
    
    • a nice line of shoes
23. a commercial organization serving as a common carrier
24. space for one line of print (one column wide and 1/14 inch deep) used to measure advertising;
    agate line
25. the maximum credit that a customer is allowed;
    credit line, line of credit, bank line, personal credit line, personal line of credit
26. a succession of notes forming a distinctive sequence;
    tune, melody, air, strain, melodic line, melodic phrase
    
    • she was humming an air from Beethoven
27. a short personal letter;
    note, short letter, billet
    
    • drop me a line when you get there
28. a conceptual separation or distinction;
    dividing line, demarcation, contrast
    
    • there is a narrow line between sanity and insanity
29. mechanical system in a factory whereby an article is conveyed through sites at which successive operations are performed on it;
    production line, assembly line

v.

1. be in line with; form a line along;
   run along
   
   • trees line the riverbank
2. cover the interior of
   
   • line the gloves
   • line a chimney
3. make a mark or lines on a surface;
   trace, draw, describe, delineate
   
   • draw a line
   • trace the outline of a figure in the sand
4. mark with lines
   
   • sorrow had lined his face
5. fill plentifully
   
   • line one's pockets
6. reinforce with fabric
   
   • lined books are more enduring