Definition 1 of 1
It minns to give one tight slap with inverted hand. Think of a Wimbledon-shtyle strong backhand, and you pretty much have the technique down pat.
Known to be more painful for the slapee than a normal slap, and often leaves a fairly big hand print on the affected cheek for a week or so.
"Saala koi roadside lafanga mujhe tanng karne ki koshish kar raha tha, maine toh ulte haath ka thappad maar diya usko."
(Some roadside rowdy was trying to to trouble me today, I gave him one tight slap, back hand style)
Added 2011-10-20 by Surdie Birdie