***These terms could differ depending on area. the term Nation e.g. Yorta Yorta nation is becoming a more common term to define Aboriginal mob. In some resources “language group” is used to determine state groupings such as Koorie, Nunga and Murri***
Mob
‘Mob’ is a colloquial term identifying a group of Aboriginal people associated with a particular place or country. It is used to connect and identify who an Aboriginal person is and where they are from. Mob can represent your family group, clan group or wider Aboriginal community group.
Clan/Language group
Indigenous nations cover wide geographical areas, and have distinct borders. Within these nations there are clan groups. Clans are larger than a family but based on family links through a common ancestry. Clan groups share a common language and kinship system, which is based on either patrilineal or matrilineal lines of descent. A clan can also be referred to as a language group. For example, the Yorta Yorta nation has several clans including Bangerang, Moira and Ulupna. Gunditjmara comprises the following language groups – Dhauwurd Wurrung, Wooloowoorroong, Kee woorroong, Koornkopanoot, Peek woorroong, Keerray woorroong, Tyakoort Woorroong and Gadubanud
Tribe
Tribe refers to a culturally distinct group of people associated with a culturally defined area of land or country. A tribe, in the Aboriginal context, is a group of people related by genealogy, a common language and occupying (or traditionally occupying) a recognised area of country.
‘Tribe’ is a European word that tends to imply western preconceptions developed from colonial experiences. ‘Nation’, ‘community’, ‘people’, ‘mob’ or the local language or culture group name is usually preferable to ‘tribe’.
See the attached PDF below "Appropriate Terminology, Indigenous Australian Peoples"