1. Work, effort and energy that is put into a project or an undertaking: It is obvious that a great deal of labor went into the building of the Egyptian pyramids.
2. The process of giving birth including the discomfort and pain associated with giving birth: Haley went into labor four hours before her little girl was born.
3. Toil, work, or physical endeavor: James survived his labors in the coal mines for four decades.