noun
1. : soap of a semifluid consistency made principally with potash or with soda by control of the fluidity by other factors (as the unsaturation of the fat used and the amount of water and glycerol present) and used chiefly in liquid soaps, in blending with hard soaps to increase solubility and lathering properties, and in medicine — see green soap
2. : the art or device of persuasion and flattery : blarney
the master of the glad hand and the soft soap — H.A.Burton