Gain access to thousands of additional definitions and advanced search features—ad free! JOIN NOW
: a parasympathomimetic drug administered in the form of its crystalline chloride C8H18ClNO2 especially to diagnose hypersensitivity of the bronchial air passages (as in asthma) — see mecholyl, provocholine
Resources for methacholine
Comments on methacholine
What made you want to look up methacholine? Please tell us where you read or heard it (including the quote, if possible).
the setting in which something occurs
Get Word of the Day daily email!
Musical Words Quiz
Test your knowledge - and maybe learn something along the way.
Test Your Knowledge - and learn some interesting things along the way.
Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!
How a folk song became a term of derision.
Sorry, not sorry
The participle made famous by Elvis
A not-so-sarcastic history
And is one way more correct than the others?
The story of an imaginary word that managed to sneak past our editors and enter the dictionary.
How to use a word that (literally) drives some people nuts.
The awkward case of 'his or her'
A quiz in common time.
SCRABBLE® fans, sharpen your skills!