Livre d'Or

It's an institution in Australian Indigenous groups (to which, for the record, I do not belong; I just thought this ought to be stated). Pretty much all adults of the clan are 'aunty'/'uncle'. And I believe, although I am not certain, that in urban areas where groups of origin are more mixed, the term extends beyond peoples of origin to the significant adults in the area or group.

I know that 'Aunty' is used as a formal honorific when introducing indigenous leaders. It seems to me that men are less likely to be introduced in media and public fora as 'Uncle so-and-so', but I've actually rarely been at an event where a male elder was invited to do the welcome to country, etc.