sap·​o·​na·​ceous ˌsa-pə-ˈnā-shəs How to pronounce saponaceous (audio)
: resembling or having the qualities of soap
saponaceousness noun

Did you know?

Saponaceous is a New Latin borrowing by scientists that is based on sapo, the Latin word for "soap." It describes natural substances, like aloe gel or some plant roots, used in making soap or having the properties of soap. It also describes things that feel or appear soapy-for example, some shales and clays, mica, and certain chemical preparations. In the 19th century, saponaceous began to be used for people having a slippery, evasive, or elusive character. One famous example is the elocutionist Bishop Wilberforce whom British politician Benjamin Disraeli described as "unctuous, oleaginous, saponaceous." In The Devil's Dictionary, author Ambrose Bierce uses Disraeli's quote to illustrate the word oleaginous, noting that "the good prelate was ever afterward known as Soapy Sam."

Word History


New Latin saponaceus, from Latin sapon-, sapo soap, of Germanic origin; akin to Old English sāpe soap

First Known Use

1710, in the meaning defined above

Time Traveler
The first known use of saponaceous was in 1710


Dictionary Entries Near saponaceous

Cite this Entry

“Saponaceous.” Dictionary, Merriam-Webster, Accessed 12 Jun. 2024.

Medical Definition


sap·​o·​na·​ceous ˌsap-ə-ˈnā-shəs How to pronounce saponaceous (audio)
: resembling or having the qualities of soap
a saponaceous preparation
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!