A university student union has officially declared what costumes are deemed too offensive to wear this Halloween.

And the list is bad news for anyone planning to celebrate the holiday dressed as a Japanese Geisha or Caitlyn Jenner; or for those thinking about wearing a turban or Native American headdress.

The comprehensive list of unsociable outfits for a Halloween party was shared by the Brock University Students' Union.

A university student union has officially declared what costumes are deemed too offensive to wear this Halloween, which includes Day of the Dead inspired outfits (pictured)

In addition to the aforementioned costumes, people are told not to wear: Day of the Dead inspired outfits, blackface, traditional Indian bindis, or thobes.

Bill Cosby and Robin Williams outfits are a no-no, as is any attire that 'makes fun of rape or suicide'.

Students are also told not to use the Confederate flag in their costumes in any way, or turn up in anything that 'represents a cultures' traditional dress'.

'It is our priority to maintain a campus climate that prevents costumes reinforcing harmful stereotypes around race, gender, culture and mental health,' a statement from the Canadian university student group reads.

Native American outfits (left) are also on the offensive list, as well as anything with the Confederate flag (right)

The Brock University Students' Union also decided that geisha outfits (left) are out of bounds, along with anything that features the traditional Indian bindi on someone's forehead

'Vetting Halloween costumes isn’t a matter of telling people what to wear. It’s a matter of paying respect to the stories and experiences of marginalized groups who are depicted in these costumes: their culture, history and lives should never be desecrated, but understood and celebrated.'

The union also created a infographic detailing the steps of thought involved in whether a costume should or should not be worn.

Many of the costumes included on the list are widely sold and worn, with one online shop even running out of stock for its Caitlyn Jenner outfit.

Blackface, as worn by this person who appears to be distastefully dressed as Trayvon Martin, is on the banned list. So are Caitlyn Jenner costume

The university's student union says people cannot attend its official Halloween party dressed in a Bill Cosby costume