: a mucolytic agent C5H9NO3S used especially to reduce the viscosity of abnormally viscid respiratory tract secretions see mucomyst

Browse Nearby Words

Cite this Entry

“Acetylcysteine.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/acetylcysteine. Accessed 7 Jul. 2026.

Love words? Need even more definitions?

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