Meanwhile, I refer to one of my father’s second cousins as my uncle. It completely depends on context, even in more strict cultures around this. If someone is close enough to the family they can be an aunt or uncle even if their relation is more distant.

I'm a bit surprised you've never heard of the spouse of a parental sibling called an uncle as well. To make that more explicit: my father's sister is my aunt, and her husband is my uncle.

In my family every single male relative is an uncle(and every female is an aunt).