1.
A card-carrying member of a particular group or political party is an official member of that group or party, rather than someone who supports it.
I’ve been a card-carrying member of the Labour party for five years.
ADJ : ADJ n
2.
If you describe someone as, for example, a card-carrying feminist, you are emphasizing the fact that they believe strongly in and try to carry out the ideas of feminism.
ADJ : ADJ n [ emphasis ]