Merriam-Webster's Collegiate® Dictionary, 11th Edition
LABOR
I. noun see: sleep
Date: 14th century
1. expenditure of physical or mental effort especially when difficult or compulsory, b. human activity that provides the goods or services in an economy, the services performed by workers for wages as distinguished from those rendered by entrepreneurs for profits, the physical activities (as dilation of the cervix and contraction of the uterus) involved in giving birth, an act or process requiring labor ; task , a product of labor,
4. an economic group comprising those who do manual labor or work for wages, b. workers employed in an establishment, workers available for employment, the organizations or officials representing groups of workers, the Labour party of the United Kingdom or of another part of the Commonwealth of Nations, see: work
II. verb (labored; laboring)
Date: 14th century
intransitive verb to exert one's powers of body or mind especially with painful or strenuous effort ; work , to move with great effort , to be in the labor of giving birth, to suffer from some disadvantage or distress , to pitch or roll heavily, transitive verb
1. archaic to spend labor on or produce by labor, to strive to effect or achieve, to treat or work out in often laborious detail , distress , burden , to cause to labor,
III. adjective
Date: 1640
of or relating to labor, of, relating to, or constituting a political party held to represent the interests of workers or made up largely of organized labor groups