Merriam-Webster's Word of the Day for January 29, 2010 is:

yellow-dog • \yel-oh-DAWG\ • adjective
1 : mean, contemptible *2 : of or relating to opposition to trade unionism or a labor union


Example sentence:
The workers were all bound under yellow-dog agreements, so they weren't able to appeal to any union forces to help renegotiate their contract.


Did you know?
In the 19th century, the noun "yellow dog" developed a derogatory sense, meaning a low, despicable person. This usage probably came about from the traditional association of the color yellow with cowardice. Just before the turn of the century, "yellow-dog" started to be used by writers who were derogatorily describing organizations that expressed opposition to trade unions. The popularized term "yellow-dog contract" referred to an agreement made by an employer and employee in which the employee agrees not to join a labor union during the time he or she is employed. While such contracts proliferated in the 1920s, they were later made unenforceable in U.S. federal courts under the Norris-LaGuardia Act (1932).

*Indicates the sense illustrated in the example sentence.