shark week

A jocular reference to Shark Week, an annual week-long marathon of shark-related programming on Discovery Channel, which, like a menstrual period, is bloody.

shark week (countable and uncountable, plural shark weeks)

1. (informal, humorous) The week when a woman menstruates.
   • 2008, Coco Tanaka, "Shark Week!", LA CityBeat, Volume 6, Number 36, 4 September 2008 - 10 September 2008, page 17:

     There are several ways to green your Shark Week, ranging from bare-minimum "shucks, why not?" consciousness to Burning Man aggro hippie.

   • 2012, Dan Savage, "Hotel room clean-up", Now (Toronto), Volume 31, Number 29, 15 March 2012 - 21 March 2012, page 102:

     If you've booked a hotel room, STAIN, and it's shark week for the wife, or a certain former senator drops in (drops out?) when you have anal sex, there's always the option of bringing your own santorum- and/or menstrual-blood-coloured/stained towels from home.

   • 2014, Michael Walsh, "Christening the backyard," Catalyst Magazine (RMIT University), Volume 70, Issue 2, April 2014, page 43:

     Imagine my shock at discovering what those little bins with the flaps in bathrooms were really for, or that when girls mentioned shark week they didn't mean there was a Jaws marathon on SBS.

• See also Thesaurus:menstruation.