please excuse me , but even people in india ?...duhkham , it is a sanskrit word , equateing to suffering in the same sence as buddha used it , so sorry to contradict but I am afraid they did know what it meant ...... dissquietitude . unsteadiness . and is often translated in just this way allso from palli .(how ever I understand the mistake as very little is taught about pre buddhist india within the buddhist tradition)
sorry this part I dont quite understand ?......sunyata is not about the fleeting nature , but is about the un steady nature , the illusive nature , the un satisfactory nature , ..thus suffering!
so I am assuming that you are meaning "dependent origination" is that in order to originate there must be an origin ,