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Caitlyn Jenner, formerly known as 1970s Olympic athlete Bruce Jenner, has announced she is transgender, appearing on the cover of Vanity Fair magazine. It's fair to say many people don't know how to speak to or about transgender people. So what do the terms involved mean and what's considered polite?

Transgender

This is an umbrella term for people whose gender is different from their "assigned" sex at birth - that written on their birth certificate. Gender can refer to one's own, internal sense of being a man or woman, or another type that doesn't fit either category. Gender can also be expressed externally - through clothing, behaviour, body characteristics and so on. Transgender can be shortened to "trans".

In 2010, the Gender Identity Research and Education Society estimated the number of trans people in the UK to be between 300,000 and 500,000.

Gender is different from sexual orientation. Transgender people can be of any sexuality.

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Transsexual

This is a term used by some people who permanently change their bodies, usually, but not always, using hormones or surgery. But some people who go through this process - known as the "transition" - prefer to be known simply as transgender, rather than transsexual. It's best to ask which people prefer.

Non-binary

Non-binary people are those who don't feel male or female. They may feel like both or like something in between. They may have a gender that changes over time or they may not relate to gender at all.

Cisgender

This describes someone who is not transgender. For instance, someone who is named a boy at birth and continues to live as a man would be cisgender. This covers the majority of the population.

"He" or "she"?

Using the appropriate pronouns when talking to someone who is transgender works on the basis of respect for the individual. Generally the name the person chooses to use indicates their gender preference. So, a transgender person called Steve would be referred to as "he", while another called Rachel would be "she". But if you are unsure, it's best to ask the person politely how they wish to be known.

This is especially so if you suspect someone identifies as non-binary, in which case a neutral term like "they" may be more appropriate.

Transgender man/transgender woman

People assigned female at birth but living as a man may describe themselves as a "transgender man", while those assigned male at birth but living as a woman may call themselves a "transgender woman". These terms can be shortened to "trans man" or "trans woman".

Some may also use the acronyms FtM (female-to-male) and MtF (male-to-female). Many prefer simply to be identified simply as a "man" or a "woman".

Cross-dresser

This describes a person who wears the clothes usually associated with the "opposite "sex. This is seen as a form of gender expression. The word "transvestite" is not used much these days. And the expression "drag queen" is different, meaning a man who dresses "as a woman" for purposes of entertainment.

'Ask. Listen. Respect'

Journalist and campaigner Jane Fae suggests it doesn't have to be complicated dealing with transgender terms. "People are individuals," she says. "Ask politely, listen to what individuals have to say and respect what they tell you.

"It's a principle and an approach to life that will take you a long way - and not just with the transgender community."

More complexity

The terms discussed here apply widely in the UK. They may not cover all situations. As transgender activists acknowledge, it is a complex area, which can be difficult for those less than fully versed in a vast range of terms to negotiate. For extra information BBC Radio One has compiled more detail on pronouns, while the US pressure group GLAAD has created a fuller glossary. Trans Media Watch has also compiled a guide to non-binary.

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