An American Holiday celebrated the first Monday in September.

There are many definitions for labor. The most accepted is "work".
 Here are the most accepted and used.

1.  
   1. Physical or mental exertion, especially when difficult or exhausting; work.
   2. Something produced by work.
2. A specific task.
3. A particular form of work or method of working: manual labor.
4. Work for wages.
5.  
   1. Workers considered as a group.
   2. The trade union movement, especially its officials.
       Source: The American Heritage® Dictionary of the English Language, Fourth Edition
      Copyright © 2000 by Houghton Mifflin Company.

The Central Labor Union urged labor organizations in other cities to follow their example of a "workingmen's holiday". The idea spread. The first municipal ordinances were passed during 1885 and 1886. The first state bill to become law was passed by Oregon on February 2l, l887. It is now celebrated as a national holiday in all 50 states. Without the labor of many we would have not advanced in society, culture, or economics. Everyone who can takes a vacation on the first Monday of September. Friends and families gather, and clog the highways, and the picnic grounds, and their own backyards and say farewell to summer.
Today, Labor Day is observed not only in the U.S. but also in Canada,
and in other industrialized nations. While it is a general holiday
in the United States, its roots in the working
class remain clearer in European countries.
squares are 130x130.the top row are mine to share.