Delbert, in this example that Don has questioned, there is an important distinction between 'preference' and 'orientation'. The word 'preference' suggests that the trait is chosen and can be 'switched off'. However, for LGBTQI people, this is not the case. Their sexual orientation is inherently a part of them and cannot be 'switched off' or chosen. It would be the same as saying your eye colour is a preference - your eye colour is something you are born with and cannot be changed.

So my point is that in this example, meanings are not changing, they are being better defined so that everyone is clear on the reality of the situation and can better understand another person's lived experience.