In Sri Caitanya Bhagavat, Mother Sachi is addressed as Āi. This name is very short but extremely powerful. It is mentioned twice in the book (2.22.42 and 3.4.268) that even if one utters the word Āi as a mundane word, still, by the influence of the word Āi one will be freed from all suffering (dukhanivaaran) and will attain pure love of Godhead (premaprapti). Also, it is mentioned that the word Āi represents the cumulative Vātsalya rasa possessed by Sachi, Yashoda, Devaki, Kausalya, Devahuti, Aditi, Prishni, and Anusuya.
You will be surprised to know that this short and powerful mantra Āi is included in Nitāi’s Name as a fraction of it. Thus, when You write or sing Nitāi, You get the benefit of chanting Āi’s Name as well along with an opportunity of relishing the pure nectar of Vātsalya rasa.
Therefore, Joy निताइ !