soapbark
noun
soap·bark
ˈsōp-ˌbärk 
: a Chilean tree (Quillaja saponaria of the family Quillajaceae, the soapbark family) with glossy leaves and terminal white flowers
also
: its saponin-rich bark used in cleaning and in emulsifying oils
Examples of soapbark in a Sentence
Recent Examples on the Web
Its adjuvant, called AS01, is derived from the Chilean soapbark tree and has also been used at a higher dose in the company's Shingrix vaccine.
—
Alexander Tin, CBS News, 3 May 2023
The soapbark tree is native to Chile.
—Bruce Y. Lee, Forbes, 15 July 2022
In fact, the AS01B adjuvant in the Shingrix vaccine (the recombinant herpes zoster vaccine to prevent Shingles) includes QS-21, which is also extracted from the Chilean soapbark tree.
—Bruce Y. Lee, Forbes, 15 July 2022
Matrix-M relies on quillaja extract from soapbark trees.
—Sarah Jane Tribble, baltimoresun.com, 19 July 2021
Matrix-M is made from the bark of the soapbark tree, which is abundant in Chile.
—Justin Meneguzzi, National Geographic, 13 Nov. 2020
Though the company has deemed the soapbark adjuvant as safe, it has not yet been evaluated as part of a final product submitted to the U.S. Food and Drug Administration.
—Justin Meneguzzi, National Geographic, 13 Nov. 2020
The rare Chilean soapbark tree produces compounds that can help boost the body’s reaction to vaccines.
—Brendan Borrell, The Atlantic, 21 Oct. 2020
This was it: a Chilean soapbark, one of a handful planted on the Berkeley campus starting in the late 1800s.
—Brendan Borrell, The Atlantic, 21 Oct. 2020
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Alexander Tin, CBS News, 3 May 2023
The soapbark tree is native to Chile.
—Bruce Y. Lee, Forbes, 15 July 2022
In fact, the AS01B adjuvant in the Shingrix vaccine (the recombinant herpes zoster vaccine to prevent Shingles) includes QS-21, which is also extracted from the Chilean soapbark tree.
—Bruce Y. Lee, Forbes, 15 July 2022
Matrix-M relies on quillaja extract from soapbark trees.
—Sarah Jane Tribble, baltimoresun.com, 19 July 2021
Matrix-M is made from the bark of the soapbark tree, which is abundant in Chile.
—Justin Meneguzzi, National Geographic, 13 Nov. 2020
Though the company has deemed the soapbark adjuvant as safe, it has not yet been evaluated as part of a final product submitted to the U.S. Food and Drug Administration.
—Justin Meneguzzi, National Geographic, 13 Nov. 2020
The rare Chilean soapbark tree produces compounds that can help boost the body’s reaction to vaccines.
—Brendan Borrell, The Atlantic, 21 Oct. 2020
This was it: a Chilean soapbark, one of a handful planted on the Berkeley campus starting in the late 1800s.
—Brendan Borrell, The Atlantic, 21 Oct. 2020
Cite this Entry
“Soapbark.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/soapbark. Accessed 22 May. 2025.
Copy CitationMedical Definition
soapbark
noun
soap·bark
ˈsōp-ˌbärk
1
: a Chilean tree of the genus Quillaja (Q. saponaria) with shiny leaves and white flowers
2
: the saponin-rich bark of the soapbark tree used in cleaning and in emulsifying oil
called also quillaja
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