backhanded

Short definition from Wiktionary

Adjective

1. 1
   With the back of the hand.
2. 2
   Involving a backward flip of the hand.
3. 3
   Insincere, sarcastic, ironic, or self-contradictory.
4. 4
   Indirect.
5. 5
   Backwards, turned around.
6. 6
   inclining to the left
7. 7
   Retrospective, occurring after the fact rather than in advance.
8. 8
   Self-serving, corrupt, slipshod, or neglectful.

Verb

1. 1
   simple past and past participle of backhand

Adverb

1. 1
   In a backhanded manner.