'Sardonic' links to Sardinia and a plant believed to cause grimacing that resembled bitter laughter.
Grimly mocking or cynical; disdainfully humorous.
From French 'sardonique,' from Latin 'sardonius,' from Greek 'sardonios' (bitter, scornful — producing a grimace). The ancient Greeks believed a plant from Sardinia (Greek 'Sardō') caused violent facial contractions resembling bitter laughter when eaten — the face was forced into a rictus grin even as the victim suffered or died. This horrifying image gave the Greeks a word for laughter that masks pain or contempt