Chambers's Twentieth Century Dictionary…
“ Soap, sōp, n. a compound of oils or fats with soda (hard soaps) or potash (soft soaps) , used in washing: (slang) soft words, flattery: (U.S. slang) money used for bribery and other secret political purposes.—v.t. to rub or wash with soap: to flatter.—ns. Soap′-ball, soap made into a ball, often with starch, as an emollient; Soap′berry, the fruit of several species of trees belonging to the genus Sapindus, containing a pulp useful as a substitute for soap in washing; Soap′-boil′er, one whose occupation is to make soap; Soap′-boil′ing, the occupation of making soap ”
