word: sardonic

Elizabeth had never been popular, indeed the more perceptive of the Meryton ladies occasionally suspected that Miss Lizzy was privately laughing at them. They also accused her of being sardonic, and although there was uncertainty about the meaning of the word, they knew that it was not a desirable quality in a woman, being one which gentlemen particularly disliked. (Death Comes to Pemberley, 9; emphasis mine)

I began (with cautious optimism) P.D. James' nod to Austen this evening. When I came across the passage above, I knew that I must share it in a featured-word post. 

From the OED (vol. 8, part 2, 1914) -

Sardonic, adj.
Of laughter, a smile: Bitter, scornful, mocking. Hence of a person, personal attribute, etc.: Characterized by or exhibiting bitterness, scorn or mockery. (111)