The deed that Hedda refest to here is what she thinks is Lovborg’s suicide.
Hedda, while talking to Brack, characterizes Lovborg's suicide as "<em>the last great act</em>", claiming that she admires that "<em>he should have the will and the strength to turn away from the banquet of life</em>".
She believes that Lovborg was brave upon deciding to take his own life so young, as the quote clearly states ("a deed of deliberate courage".)
