The word “indigenous” (small “i”) is an adjective, meaning, “originating or occurring naturally in a particular place; native.” (dictionary.com). It can be used to describe anything that has originated from somewhere, with regards to the place it originated from. For example, the kangaroo species is indigenous to Australia.
When describing humans who are indigenous to a particular country, region, or other area of land, the capitalised form, “Indigenous” (capital “I”) is often used as a noun to identify exactly which set or subset of people are being talked about. For example, Aboriginal and Torres Strait Islander peoples are the Indigenous peoples of Australia.
Things can become confusing when people either don’t understand, or chose to misrepresent, the meaning of the word, or the context it’s used in. For example, people who are born in Australia and may represent the latest in a successive number of generations of their family born within Australia, sometimes argue that they are as “indigenous” as Aboriginal or Torres Strait Islander peoples. The error in statements such as this is they ignore the “origin” part of the definition; that is, if the origin of their family lineage is from somewhere other than Australia, then by definition they cannot be indigenous to Australia. It would be like saying that a kangaroo that is born in a zoo in another country makes that kangaroo and any of its subsequent offspring indigenous to that country.
It can also be confusing when “Indigenous” is used as a noun because as a name in itself is does not reveal anything specific about the person or group it represents. For example, a person could say they are “Indigenous”, however that does not provide any information about which cultural group they belong to; it doesn’t even tell me which part of the world they are from. While “Indigenous” is often used as a term of convenience, for example as a means of distinguishing between “Indigenous” and “non-Indigenous” peoples of a community, it also risks the loss of recognition of the unique differences between peoples within the group it aims to identify. For example, you could talk generically about the social justice issues faced by Indigenous peoples worldwide, yet this does not necessarily mean that the specific issues faced by one segment of this group (eg: Aboriginal peoples) are exactly the same, and therefore should be addressed in exactly the same manner, as any other segment of the group (eg: Māori peoples).
One strategy to avoid confusion when using the term “Indigenous” is to define which group(s) of people you are referring to while you are using the term. For example, in a written document you might commence with a statement like:
For the purposes of this document, the term Indigenous is used to refer to Aboriginal and Torres Strait Islander peoples collectively, unless otherwise stated.
Another strategy is to avoid using the term altogether, and instead specify exactly who you are referring to. For example:
The total population of Aboriginal and Torres Strait Islander peoples currently residing in New South Wales is …
The best strategy, however, is to ask the people who you are discussing what they prefer to be called.