azad·​i·​rach·​tin | \ ə-ˌza-də-ˈrak-tən How to pronounce azadirachtin (audio) \
plural azadirachtins

Definition of azadirachtin

: a chemical compound C35H44O16 that occurs in the seeds of the neem tree (Azadirachta indica) and is used as an insecticide Most of neem's pesticidal punch comes from the compound azadirachtin, which disrupts insects' growth as well as dampening their appetite.— Leslie Land, New York Times, 10 May 2007 Azadirachtin causes hormonal imbalances and disrupts the maturation cycle in insects, which results in unsuccessful molts, or heavily deformed immature insect stages.— Illinois Blasdel, Landscape Management, April 2005

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

First Known Use of azadirachtin

1971, in the meaning defined above

Keep scrolling for more

Learn More about azadirachtin

Time Traveler for azadirachtin

Time Traveler

The first known use of azadirachtin was in 1971

See more words from the same year

Statistics for azadirachtin

Cite this Entry

“Azadirachtin.” Dictionary, Merriam-Webster, Accessed 15 Jun. 2021.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon


Test Your Vocabulary

Name that Thing: Dog Breeds

Name That Thing

Test your visual vocabulary with our 10-question challenge!

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

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