This is the 2008th most frequent French word.
bah
"Bah" is an informal French expression used to convey indifference, hesitation, or dismissal, equivalent to "well," "meh," or "whatever" in English.
Here, 'bah' is used as a filler word to express hesitation or doubt.
Bah, je ne suis pas sûr de ce que tu veux dire.
Well, I'm not sure what you mean.
In this case, 'bah' expresses mild emphasis, conveying that the statement is self-evident to the speaker.
Bah, c'est évident qu'il faut essayer encore une fois.
Well, it's obvious that we need to try again.
Here, 'bah' conveys slight disagreement or disbelief in response to the comment.