beer o'clock

noun2

1. •
   (slang, humorous) The time of the first beer (or alcoholic beverage) of the day.

   • Pack an esky with ice-cold bottles of Cooper's Green Label and head down to Holloways Beach, just north of Cairns, around beer o'clock on a Friday afternoon. — 1999
2. •
   (slang, humorous) Time for a beer (the first of the day or otherwise).

   • Questioner: What time is it? Answerer: It's beer o'clock.