semisynthetic

adjective

semi·​syn·​thet·​ic ˌse-mē-sin-ˈthe-tik How to pronounce semisynthetic (audio)
ˌse-ˌmī-,
-mi-
1
: produced by chemical alteration of a natural starting material
semisynthetic penicillins
2
: containing both chemically identified and complex natural ingredients
a semisynthetic diet
3
: partly synthetic
semisynthetic motor oil

Example Sentences

Recent Examples on the Web The rate of drug overdose deaths involving heroin, natural and semisynthetic opioids and methadone were lower in 2018 than the previous year. Janet Adamy, WSJ, 30 Jan. 2020 Hydrocodone and oxycodone are semisynthetic opioids used to treat pain. Author: Lindsey Bever, Anchorage Daily News, 1 Feb. 2018 Hydrocodone and oxycodone are semisynthetic opioids used to treat pain. Author: Lindsey Bever, Anchorage Daily News, 1 Feb. 2018 Hydrocodone and oxycodone are semisynthetic opioids used to treat pain. Author: Lindsey Bever, Anchorage Daily News, 1 Feb. 2018 Hydrocodone and oxycodone are semisynthetic opioids used to treat pain. Author: Lindsey Bever, Anchorage Daily News, 1 Feb. 2018 Hydrocodone and oxycodone are semisynthetic opioids used to treat pain. Author: Lindsey Bever, Anchorage Daily News, 1 Feb. 2018 Hydrocodone and oxycodone are semisynthetic opioids used to treat pain. Author: Lindsey Bever, Anchorage Daily News, 1 Feb. 2018 Hydrocodone and oxycodone are semisynthetic opioids used to treat pain. Author: Lindsey Bever, Anchorage Daily News, 1 Feb. 2018 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'semisynthetic.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1937, in the meaning defined at sense 1

Time Traveler
The first known use of semisynthetic was in 1937

Dictionary Entries Near semisynthetic

Cite this Entry

“Semisynthetic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/semisynthetic. Accessed 1 Apr. 2023.

Medical Definition

semisynthetic

adjective
semi·​syn·​thet·​ic -sin-ˈthet-ik How to pronounce semisynthetic (audio)
1
: produced by chemical alteration of a natural starting material
semisynthetic penicillins
2
: containing both chemically identified and complex natural ingredients
a semisynthetic diet
semisynthetically adverb
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