Also there are 2 sets of definitions I believe of introvert and extrovert. The traditional and the clinical one. I am not sure those are the right labels for the 2 interpretations.

And I think me and the 2 I've replying to all agree with the latter one. Which is independent of shyness or outgoingness. It's purely a mental recharge thing really. Do you feel like you need to be alone after a long time of being with other people.

This is different from the traditional view which is correlated with shyness vs outgoing charismatic view.

Also no one is ever just 1 or the other. But can be all of the above at various points at varying and ever changing degree.