Aditi is Heaven, Aditi is mid-region, 
Aditi is the Mother (Earth), Father and Son;
She is all the Gods; She is the five peoples;
Aditi is all that is born and what is to be.

She is the goddess of infinity as the verse (1.89.10) given below unambiguously declares.

The five peoples are the beings of the five planes of matter (earth), prāāņa (mid-region), manas  (heaven), svar (world of light) and ānanda (the world of bliss). This verse is also the invocation to the Prashņa upanishad.

To understand Aditi, we have to understand the purāņic story of Kashyapa and his two wives, Diti and Aditi in a symbolic sense. Diti in the RV denotes finiteness. All the devās are called as adityāsbecause they are descended from Aditi. RV makes several interesting references to Diti and Aditi together, as in (4.2.11).

Mitra, Varuņa, in the uprising of the Sun, you ascend;
You behold the Infinite Aditi and the finite Diti. (7.62.8).

May we abide in the law of thy workings and be blameless before the Mother infinity aditaye. (1.24.15).

Aditi is the Mother of all, Mother of all the Gods, Mother of all creation. She is the infinite consciousness. We can become blameless only by rejecting all things that are contrary to the Supreme Law.