eager beaver
'> : something resembling a cushion: such as
: a pad of springy rubber along the inside of the rim of a billiard table
: a padded insert in a shoe
: an elastic body for reducing shock
: a mat laid under a large rug to ease the effect of wear
: something (such as an economic factor or a medical procedure) serving to mitigate the effects of disturbances or disorders
: a reserve supply (as of money)
: a comfortable lead //a 4–0 cushion in the ninth inning