Sharp and Biting – or to borrow a vocab word from the text, "piquant."
Just read any exchange between Hedda and Brack – like this one:
HEDDA: I’ve been up in my room dressing […]. BRACK: And there’s not the least little crack in the door […]? HEDDA: You forgot to arrange it. BRACK: [How] stupid of me.
Seriously, you could dice vegetables with this dialogue. Much of the play’s dialogue is characterized by this sort of sharp, witty exchange, much of it coming from Hedda. In addition, there’s quite a bit of wordplay in the original language that doesn’t quite come across in English. (Check out the Hedda-Brack exchange about the couple on the train and a third person coming aboard; the translation isn’t bad, but it feels a little strained.) On the other hand, some of this wordplay translates beautifully:
HEDDA: I used Tesman as my escort home from parties last summer— BRACK: Unfortunately—I was headed quite a different way. HEDDA: How true. Yes, you went several different ways last summer.