The word ‘advaita’ is a very important word. It's a word that negates dvaita, which means ‘two.’ The ‘a’ is a negative particle, so the meaning would be ‘that which is nondual.’ And it reveals the philosophy that all that is here is One, which means that there is nothing other than that One, nor is it made up of any parts. It's a whole without parts, and That they call ‘Brahman’ (the Absolute), and That you are – because the nondual cannot be different from you, the inquirer. If it is different from you, then it is dual; then you are the subject and it is the object. So it has got to be you. And therefore, if you don't recognize that, you'll miss out on being the Whole.
Swami Dayananda Saraswati
(Source: What is enlightenment magazine. From a series of dialogues between Swami Dayananda and Andrew Cohen in February 1998.)
(Swami Dayananda Saraswati is a disciple of Swami Chinmayananda)