Intrepid: Reckless? Fearless? Daring?

At any rate, I have often wondered precisely the same thing: WHY would Darcy say this to Miss Bingley? Since he said it with great intrepidity (I'm going to go with fearlessness), we know it did not just slip out. Did he think Miss Bingley would not believe him? Or did Darcy think that Miss Bingley would believe he was making sport of Elizabeth?

I lean toward the latter, because we know from earlier in this chapter - the ON tells us - that no sooner had he made it clear to himself and his friends that she had hardly a good feature in her face, than he began to find it was rendered uncommonly intelligent by the beautiful expression of her dark eyes. So we can assume that Miss Bingley has heard his disparaging views of Elizabeth's looks from his own mouth (unless he made that admision only to Bingley and Hurst). And she might have already teased Darcy about his slight of Elizabeth at the Assembly, which Elizabeth herself told "with great spirt among her friends" so the story might well have made it back to Miss Bingley by this time.

The fact that Darcy listens to Miss Bingley "with perfect indifference" says to me that this is the kind of banter Darcy and Miss Bingley have engaged in before or might routinely engage in. As the author said: "her wit flowed long" and we know that Miss Bingley could be agreeable company and that Darcy is clever (ch 4). In fact, we do not know - as some assume - that Darcy dislikes Miss Bingley! If I am not mistaken, this is the first time a conversation between them is reported. To me, they seem to be engaged in coversation between two people of like minds: Miss Bingley certainly thinks she knows what is on his mind, and that they share the same opinions. She is not hesitant to tease him, giving me the impression that she knows him well enough to do so, and he allows her to tease him seemingly without any affront on his part!