To execute a backhand stroke or throw

To slap with the back of one's hand

With the back of the hand.

Involving a backward flip of the hand.

Insincere, sarcastic, ironic, or self-contradictory.

Indirect.

Backwards, turned around.

(of writing) inclining to the left

Retrospective, occurring after the fact rather than in advance.

Self-serving, corrupt, slipshod, or neglectful.

In a backhanded manner.