{pa'logh} "the past" is a pun on the German word "damals", which means something like "back then". "Da" is also German for "there", and "-mal" is used in German to talk about doing something X number of times ("zweimal" = "two times, twice" etc.) So "there" + "times" in Klingon is {pa'} + {-logh} = {pa'logh}.