worker

n. employee; laborer, one who works in manual labor

In economics, labour (or labor) is a measure of the work done by human beings. It is conventionally contrasted with such other factors of production as land and capital. There are theories which have created a concept called human capital (referring to the skills that workers possess, not necessarily their actual work), although there are also counter posing macro-economic system theories that think human capital is a contradiction in terms.
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Noun
1. a person who works at a specific occupation; "he is a good worker"
(antonym) nonworker
(hypernym) person, individual, someone, somebody, mortal, human, soul
(hyponym) caster
(derivation) work, do work
2. a member of the working class (not necessarily employed); "workers of the world--unite!"
(synonym) proletarian, prole
(hypernym) commoner, common man, common person
(member-holonym) labor, labour, working class, proletariat
3. sterile member of a colony of social insects that forages for food and cares for the larvae
(hypernym) insect
(hyponym) soldier
(derivation) work
4. a person who acts and gets things done; "he's a principal actor in this affair"; "when you want something done get a doer"; "he's a miracle worker"
(synonym) actor, doer
(hypernym) person, individual, someone, somebody, mortal, human, soul
(hyponym) demon
(derivation) work

(n.)
One who, or that which, works; a laborer; a performer; as, a worker in brass.
  

(n.)
One of the neuter, or sterile, individuals of the social ants, bees, and white ants. The workers are generally females having the sexual organs imperfectly developed. See Ant, and White ant, under White.
  

Any railroad employee assigned to inspect, test, repair, or service railroad rolling equipment, or their components, including brake systems. Members of train and yard crews are excluded except when assigned such work on railroad rolling equipment that is not part of the train or yard movement they have been called to operate (or been assigned to as "utility employees"). Utility employees assigned to and functioning as temporary members of a specific train or yard crew (subject to the conditions set forth in 49 CFR 218.22), are excluded only when so assigned and functioning. (49CFR218)