Analogies are great but I like to keep it more relative...
it basically is gender dysphoria and those two words sum it up quite well when broken down.
If they can't answer the question "what is gender?", fill them in...
expressing how it includes the concept of gender identity, the self perception between the masculine and feminine and how this self perception is different to our biological sex.. thus creating a dysphoria of self identity.
We have a gender that is the opposite to our "born" sex (body)...
and in order to correct this we require...
the use of hormones and surgery...
to realign our true core gender with a new body that matches.
We change the body to match the mind because we can't change our gender-identity but we can change our bodies and physiological make up.
Imagine someone suggesting to you that you need to change your gender.. it seems ridiculous right lol!
[good to add some humour to keep it light
]Gender Dysphoria is a condition that comes about from something that occurs during pregnancy, we develop in a different way which basically means it is something we are born with.
It is not a life-style choice nor is it something we choose to have in any way, we are born with it just like some people are born with lazy eyes or albinism.
And because of social stigmas and human nature people look differently upon us for no rational reason.