It is essentially lens shaped.  It has a back edge the entire length of the blade (also pretty unusual - usually the first 1/2 - 2/3 is flat, rounded or peaked), with the last 1/3 or so being fully sharpened. 
 
The tip, by the way, would be huabua, if it were a Thai blade.  Note the likke "beak" at the apex of the top.  I don't know what it would be called in Burmese, though.
		 
		
		
		
		
		
		
		
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