working class

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The socioeconomic class consisting of people who work for wages, especially low wages, including unskilled and semiskilled laborers and their families.

from The Century Dictionary.

• noun A collective name for those who earn their bread by manual labor, such as mechanics and laborers: generally used in the plural.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The social class of those who perform physical work for a living, as opposed to the professional or middle class, the upper class, or others.
• adjective Relating to the working class; suggestive of the working class in manner of speaking, outlook, appearance or other qualities.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a social class comprising those who do manual labor or work for wages
• adjective working for hourly wages rather than fixed (e.g. annual) salaries
• adjective of those who work for wages especially manual or industrial laborers