What is the first word

It’s hard to determine what exactly is meant to be a word and just babble when it comes from a baby. Our 8-month-old girl has said “dadadadada” but it was not really directed at me, just a sound she likes to make. I guess when she actually says a word and her face shows that she meant to say it, that’s when we’ll make it the official “first word”. But that line is blurred more and more with every new sound that comes out.