16. (adj.)labor of or pertaining to workers, their associations, or working conditions: labor reforms.
Etymology: (1250–1300; ME < MF < L labor)
Definition of 'labor'
Princeton's WordNet
1. (noun)labor, labour, working class, proletariat a socialclass comprising those who do manuallabor or work for wages "there is a shortage of skilled labor in this field"
2. (noun)labor, labour, toil productive work (especially physical work done for wages) "his labor did not require a great deal of skill"
3. (noun)parturiency, labor, labour, confinement, lying-in, travail, childbed concluding state of pregnancy; from the onset of contractions to the birth of a child "she was in labor for six hours"
4. (noun)labor movement, trade union movement, labor an organized attempt by workers to improve their status by united action (particularly via labor unions) or the leaders of this movement
5. (noun)British Labour Party, Labour Party, Labour, Labor a political party formed in GreatBritain in 1900; characterized by the promotion of labor's interests and formerly the socialization of key industries
6. (noun)Department of Labor, Labor Department, Labor, DoL the federaldepartment responsible for promoting the workingconditions of wage earners in the United States; created in 1913
7. (verb)undertaking, project, task, labor any piece of work that is undertaken or attempted "he prepared for great undertakings"
8. (verb)tug, labor, labour, push, drive strive and make an effort to reach a goal "She tugged for years to make a decent living"; "We have to push a little to make the deadline!"; "She is driving away at her doctoral thesis"
9. (verb)labor, labour, toil, fag, travail, grind, drudge, dig, moil work hard "She was digging away at her math homework"; "Lexicographers drudge all day long"
10. (verb)labor, labour undergo the efforts of childbirth
3. labor when a woman gives birth to a baby to go into labor; to be in labor; a difficult labor
4. (verb)labor to work hard He labored day and night to finish the job.
Definition of 'labor'
Webster Dictionary
1. (noun)labor physical toil or bodily exertion, especially when fatiguing, irksome, or unavoidable, in distinction from sportive exercise; hard, muscular effort directed to some useful end, as agriculture, manufactures, and like; servile toil; exertion; work
8. (noun)labor to exert muscular strength; to exert one's strength with painful effort, particularly in servile occupations; to work; to toil
9. (noun)labor to exert one's powers of mind in the prosecution of any design; to strive; to takepains
10. (noun)labor to be oppressed with difficulties or disease; to do one's work under conditions which make it especially hard, wearisome; to move slowly, as against opposition, or under a burden; to be burdened; -- often with under, and formerly with of
11. (noun)labor to be in travail; to suffer the pangs of childbirth
12. (noun)labor to pitch or roll heavily, as a ship in a turbulent sea
13. (verb)labor to work at; to work; to till; to cultivate by toil
14. (verb)labor to form or fabricate with toil, exertion, or care
15. (verb)labor to prosecute, or perfect, with effort; to urge stre/uously; as, to labor a point or argument
Definitions of labor 
