Meaningless; synonym for "
Duh."
Often and repeatedly--sometimes incessantly--used by speakers incapable of beginning an
idea at its beginning, those seeking to stall for time until a thought congeals, or those desiring a familiar starting point as they venture into the dangerous world of communication.
Beginning each sentence with "so" has been called "using a verbal
tee" to enhance
one's chances of hitting an idea squarely.