sarcastic

sarcastic
sar‧cas‧tic /sɑːˈkæstɪk $ sɑːr-/ adjective
saying things that are the opposite of what you mean, in order to make an unkind joke or to show that you are annoyed:
    Was she being sarcastic?
    sarcastic remark/comment/question
    He can’t help making sarcastic comments.
    sarcastic manner/smile/laugh etc
    ‘I thought so,’ she said with a sarcastic smile.
—sarcastically /-kli/ adverb