9 to 5

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From the common western business hours of 9:00 am to 5:00 pm.

9 to 5 (plural 9 to 5s)

1. A day job, especially at a large company, emphasizing banality.
   • 1976 March, advertisement, Popular Mechanics, page 44,

     By day, he′s a 9-to-5 man. By night, an explorer in a field that really interests him!

   • 2005 December, Zondra Hughes, “Save Your Marriage Now!: Divorce-Busters That Work”, in Ebony, page 146:

     Keisha works a 9-to-5, picks up their son from the day care and then heads home to prepare dinner for the family.

2. The workday itself (the period of the day between 9 am and 5 pm).
   • 2000, Renata Somogyi, Inner Peace in a 9-To-5 World: Attaining Enlightenment Amidst the Chaos:
   • 2006 July, Max King, “Leading Edge: It′s Good to be King”, in Running Times, page 58:

     [D]uring his heyday, Bill Rodgers emphatically stated, “No runner working 9 to 5 can beat me”, attesting that training for elite distance competition had become a full-time job in itself.

   • 2010 January-February, Lou′s Clues: Getting to Work (editorial), Ancestry Magazine, page 6,

     And you might decide that our 9-to-5s today just aren′t so tough.

3. One who works in a job from 9 am to 5 pm.
   • 2009, Scott Brown, Treat Your Poker Like a Business‎, page 101:

     Stock markets crash, businesses go bankrupt, and 9-to-5s can disappear from layoffs and downsizing.

• (day job): 9-to-5 job, nine-to-five job