sar ‧ cas ‧ m /ˈsɑːkæz ə m $ ˈsɑːr-/ BrE AmE noun [uncountable]
[ Date: 1500-1600 ; Language: French ; Origin: sarcasme , from Late Latin , from Greek sarkasmos , from sarkazein 'to tear flesh, bite your lip angrily, sneer' , from sarx 'flesh' ]
a way of speaking or writing that involves saying the opposite of what you really mean in order to make an unkind joke or to show that you are annoyed:
‘Good of you to arrive on time,’ George said, with heavy sarcasm (=very clear sarcasm) .
hint/trace/edge/touch of sarcasm
There was just a touch of sarcasm in her voice.