the week a woman experiences menstruation

The safeguarding of Earth and other worlds from biological cross-contamination (i.e. billionaires with too much time on their hands).

Also known as “planetary protection.” Planetary protection / quarantine “reflects both the unknown nature of the space environment and the desire of the scientific community to preserve the pristine nature of celestial bodies until they can be studied in detail.”

There are two types of interplanetary contamination. Forward contamination is the transfer of viable organisms from Earth to another celestial body. Back contamination is the transfer of extraterrestrial organisms, if such exist, back to the Earth's biosphere.

The week during which a woman has her period. There will be blood, an uncomfortable sense of tension and a bad tempered, unpredictable beast.

Take heed during shark week. If you show signs of weakness or aggression, you will be attacked. If you get attacked, it will be all your fault, infinitely more traumatic for her and you'll never be allowed to forget it.

A week in the summer when discovery channel broadcasts all its shows in the shark theme. The best week to watch TV.

The time of the month when you do not want to be swimming with Sharks

Shark week - A term used by female to male trans individuals, in order to reduce dysphoria triggered by using the word period, as this is gendered to be a female experience.

A week during the summer in which Discovery Channel airs its annual "Shark Week" and everyone on earth pretends to watch it and makes sure that all of their friends know by plastering stupid shit (e.g. Facebook status updates) all over the Internet. Usually no one really knows when Shark Week is until it actually happens because no one really cares about sharks any other week of the year. An overhyped show that everyone just claims they watch to look cool in front of their friends.